Analytical Applications of Voltammetry in the Determination of Heavy Metals in Soils, Plant Tissues, and Water—Prospects and Limitations in the Co-Identification of Metal Cations in Environmental Samples

Chatziathanasiou, Efthymia; Liava, Vasiliki; Golia, Evangelia E.; Girousi, Stella

doi:10.3390/analytica5030023

Open AccessArticle

Analytical Applications of Voltammetry in the Determination of Heavy Metals in Soils, Plant Tissues, and Water—Prospects and Limitations in the Co-Identification of Metal Cations in Environmental Samples

¹

Analytical Chemistry Laboratory, School of Chemistry, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece

²

Laboratory of Soil Science, School of Agriculture, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece

^*

Author to whom correspondence should be addressed.

Analytica 2024, 5(3), 358-383; https://doi.org/10.3390/analytica5030023

Submission received: 26 May 2024 / Revised: 8 July 2024 / Accepted: 25 July 2024 / Published: 2 August 2024

(This article belongs to the Special Issue Feature Papers in Analytica)

Download

Browse Figure

Versions Notes

Abstract

:

Heavy metals represent a class of chemical elements that includes metalloids, bases and transition metals, lanthanides, and actinides. They are distinguished for their toxicity in small concentrations and their negative effects on the environment and human health; consequently, their monitoring has to be improved to manage the risks. The determination of heavy metals is carried out mainly by analytical methods, using spectroscopy, spectrometry, and electroanalysis. However, the interest has shifted to new and faster methodologies and techniques for heavy metal analysis, with particular emphasis on voltammetry. Voltammetry is preferred for heavy metal detection owing to the advantages of low cost, simplicity, ease of operation, fast analysis, portability, the ability to monitor environmental samples in the field, and high sensitivity and selectivity. Therefore, this study summarizes the applications of voltammetry in heavy metal determination mainly in water, soil, and plant samples, and presents an evaluation of sensitivity, selectivity, and applicability.

Keywords:

heavy metals; voltammetry; environmental applications; differential pulse voltammetry (DPV); square wave voltammetry (SWV); water analysis

1. Introduction

1.1. Heavy Metals

The characterization of pollutants that contaminate our environment is very important in the assessment of human exposure and of ecosystem risk. Due to the extremely high number of chemicals found in the environment, the sampling and the chemical analysis of contaminated environmental samples can be time consuming and expensive, thus limiting the number of samples that can be analyzed.

During the last years, there have been increasing issues addressing the possible impact of industrial activities on the environment. Consequently, the ability to monitor contaminants in the environment has greatly improved, managing risks to human health and ecosystems. Regarding the environment, discharges related to industrial activities represent a potential threat to the ecosystem, since they contain xenobiotics like heavy metals. Heavy metals are associated with different toxic effects that may cause immediate or long-term damage to the environment and may constitute a hazard to public health; prolonged exposure to elevated levels of these metals is linked to various health issues, as presented in Figure 1. Besides this, heavy metal accumulation may result in ecosystem imbalances and biodiversity loss. As a consequence, many countries have established water quality standards that include concentration limits for heavy metals. Monitoring and detecting these metals is crucial to ensuring compliance with regulatory guidelines and protecting public health. The detection of heavy metals helps identify and trace the sources of contamination, whether they are from industrial discharges, agricultural runoff, or other anthropogenic activities. This information is essential for implementing targeted pollution control measures. Recognizing the importance of environmental analysis is crucial, as it represents a critical tool for safeguarding human health, protecting the environment, ensuring regulatory compliance, and supporting sustainable water management practices. Moreover, for assessing the potential risk for human exposure, ecosystem and water resource contamination, etc., it is important to integrate physicochemical information within ecotoxicology and biomonitoring [1,2,3,4,5,6,7,8].

1.1.1. Determination of Metal Ions in Soil Samples

The metal ion determination in soils differs from their corresponding determination in water. This is due to the fact that soil is a living organism that reacts in various ways, depending on changes in the biotic and abiotic environment [9].

The solid phase of the soil can both adsorb and desorb metal ions. Depending on the soil’s clay and organic matter content, it is possible to change the available or water-soluble concentration of these ions [10]. It is clear that the simultaneous presence of other chemical elements and substances and the duration or aging of the pollution is a decisive factor that varies the ionic state and therefore the availability of these elements to plants or their solubility to the underground aquifer [11,12].

It has been observed among several researchers that different soil orders and their specific characteristics can alter the distribution of metals in the different soil fractions as well as their ionic state [13]. It is also known that they can form complexes with a plethora of compounds, both inorganic and organic. They can also react and adsorb to pollutants or organic compounds present in the soil, either by their own construction or due to various anthropogenic activities. A typical case is the adsorption of metal ions on the surfaces of microplastics and the alteration of their total and available concentration [14].

1.1.2. Identification of Metal Ions in Plants

The quantitative determination of metals in plant tissues is quite different. Plants are often analyzed for metals that are likely to accumulate in their various parts (leaves and stems), as their differential distribution is an important aspect of controlling their metabolic processes.

In addition, metal quantification in plant roots is the subject of considerable research, as plants often accumulate metals in their underground part, contributing to one of the mechanisms of phytoremediation known as phytostabilization [15]. However, the rhizosphere environment is distinct from the remaining soil environment, as a variety of microorganisms exist and function by contributing to the process of remediation, accumulating metals and enhancing the physiological function of plants. In the flowers and seeds of many aromatic, medicinal, and energy plants, the accumulation of metals is also of interest, as due to their lipophobic nature, they are at very low levels and particularly difficult to detect [16]. However, in these parts of the plants, they promote the production of secondary metabolites of high economic and dietary value; therefore, our scientific interest is focused on the detection of metals within these, as it is possible to alter the quality of the resulting product [15]. However, the presence of micro-organisms, as well as the substances secreted by the plants and excreted by the plants through their roots, may interfere in metal detection, as they often form complex compounds [9].

1.2. Classical Methods the for Determination of Metal Ions in Soil Samples and Plants

A variety of methods are used to identify metals in soil and plant samples. The most common methods involve two stages: the first comprises the extraction of metal ions using an appropriate extracting solution. In order to determine the total metal concentration, digestion with a mixture of concentrated acids (HNO₃, HCl, HF, HClO₄), often with the addition of H₂O₂, and heating for at least two hours in a closed reflux system. A microwave oven with Teflon bombs may also be used to speed up digestion [10]. In the second step, the quantification of metals is carried out using known techniques, such as Atomic Absorption Spectroscopy, Flame or Graphite Furnace Apparatus, Emission Spectroscopy, along with voltammetric techniques [17].

Extraction of the plant samples is carried out by digesting using a mixture of Aqua Regia (HCl:HNO₃, 3:1) or just concentrated nitric acid (HNO₃). Furthermore, in several cases the plant tissue has been burnt in an oven at 500 °C for several hours and subsequently extracted with electrodeg. HNO₃. Quantification of metals in the extracts is again carried out using the same analytical techniques as for the soils.

Voltammetry—A Promising Analytical Method for Determination of Metal Ions

There is a need for analytical methodologies that are pertinent, applicable in the field, quick, and yet cost-effective, allowing sample preparation simplicity, real-time monitoring, and equipment accessibility [18,19,20,21,22,23,24,25,26]. Thus, most cost-effective and rapid field screening and monitoring methods are increasingly requested in order to provide information concerning the location, source, and concentration of pollutants that may impact human health and the environment. Voltammetry is preferred for the detection of heavy metals, possessing the advantages of low cost, simplicity, ease of operation, fast analysis, portability, the ability to monitor environmental samples in the field, and high sensitivity and selectivity. In the present review, the applications of voltammetry in the determination of heavy metals in the environment are critically summarized.

1.3. Applications of Voltammetry in the Analysis of a Single Heavy Metal

Voltammetry has been used for single heavy metal determination in various samples, as described in Table 1 and in the following sections.

1.4. Determination of Pb

The determination of lead in water samples has been studied by anodic voltammetry (ASV) using a copper-shaped carbon electrode. The electrolyte used was a buffer solution of 0.01 M HCl and 1 M KCl. The selective determination of Pb was successful by adjusting the electrodeposition potential [27]. A glassy carbon electrode modified with eDAQ (highly flexible data acquisition system) was also used in a solution of 1 M KNO₃ supporting electrolyte. The technique yielded satisfactory results in the selective determination of Pb, as the only significant inhibition was caused by an electrode. The proposed technique has a high probability of replacing conventional reagent-based sample preparation methods for the detection of Pb in tap water [28].

With square wave voltammetry (SWV), Pb has been detected in tap, well, and thermal water by forming a carbon paste electrode with geopolymer cement. A 0.2 M NaNO₃ solution was used as the electrolyte, and the results showed that the sensor offered high selectivity for Pb²⁺ [29]. Square wave voltammetry was combined with anodic stripping voltammetry (SWASV) to detect Pb²⁺ ions. A study conducted with SWASV used an electrode printed with an ink injection printer, modified with multiwalled carbon nanotubes (IJP-MW-CNT), and an electrolyte with a 0.1 M acetate buffer. The LOD of the IJP-MW-CNT sensor in drinking water was calculated to be below the maximum contamination level established by the World Health Organization (WHO) and the Environmental Protection Agency (EPA). The LOD was calculated on a drinking water sample without the need for in situ membrane formation, an electrolyte, or pH adjustment [30]. Another technique involves detecting Ρb with a lithographically printed electrode, shaped with Bi and hierarchically tubular and porous biochar (Bi/PTBC800/SPE). With 0.1 M acetate buffer and pH 4.5, and under optimal conditions, PTBC gave much better analytical performance in detecting Pb²⁺ ions compared to previous similar techniques [31]. The lithographically printed carbon electrode modified with dopamine polymer and polypyrolle hydrogel provided satisfactory results, and signal amplification was carried out with improved conductivity and catalytic capacity [32]. SWASV detected Pb in food samples with an Fe₃O₄-shaped glassy carbon electrode in a Schiff base network. As an electrolyte, a solution of 1.0 × 10⁻¹ M KNO₃ was used. The results obtained showed that this method exhibited appropriate selectivity, stability, repeatability, and reproducibility [33]. Using the same voltammetric technique, tap water samples were studied with an electrolyte of 0.1 M acetate buffer, pH 4.5. A graphene oxide electrode was used, which was modified with N and Bi. The GO Bi and N electrode showed remarkable electrocatalytic activity for the detection of Pb²⁺ compared to the individual Bi- and N-doped GO electrodes, as measured by cyclic voltammetry (CV). The formation of electroactive double positions Bi and N significantly enhances the adsorption of Pb²⁺ ions as well as the deposition-redissolution process, while their synergistic interaction in electron transfer and catalysis is responsible for the significantly sensitive detection [34]. Pb ions were found in water and soil samples near a plant with a glassy carbon electrode modified with Bi- and Bi₂O₃ and 0.1 M acetate buffer as the supporting electrolyte. This material, which preserved the structure of Bi-MOFs, had a relatively large specific surface, as well as high electron transfer capabilities. It had a wider linear range, a detection limit equal to 6.3 nM, good stability, reproducibility, and selectivity, and comparable performance to the ICP-MS method in different samples [35]. Another study used a glassy carbon electrode modified with two-dimensional blue MXene in 0.01 M phosphate buffer at pH 6.5. The electrode showed high selectivity despite the introduction of different interfering ions in the detection process of Pb²⁺ [36]. Moreover, a modified glassy carbon electrode (GCE) consisting of reduced graphene oxide, nano-flowered MoS₂, and chitosan was used for detecting Pb²⁺ in tobacco leaves. The electrochemical sensor was studied by square wave anodic stripping voltammetry (SWASV) and showed reproducibility, stability, and anti-interference ability [37]. Moreover, SWASV using a bismuth-film-modified electrode with 0.2 M acetate buffer was successfully applied for Pb determination in soil samples without interfering with non-target heavy metals such as Cu ions [38].

A recent paper used linear-sweep voltammetry (LSV) in combination with anodic stripping voltammetry (ASV). This research involved forming a carbon paste electrode with clay and detecting Pb ions in water and biological samples, using the 0.1 M KCl solution as an electrolyte. The mechanism of filtration of Pb on the surface of a ceramic microfiltration membrane, made of a mineral clay lamp, was studied. The Pb ion accumulated well on the clay membrane/electrode surface at a low pH of 1.5. At higher pH (pH > 7), Pb precipitated as Pb(OH)₂, which resulted in zero accumulation of Pb on the surface of the clay membrane of the electrode [39].

Pb has also been determined by differential pulse anodic stripping voltammetry (DPASV) in three different commercial products used as progressive hair dyes. The technique involved a cork-graphite composite sensor and two different electrolytes. The 0.5 M H₂SO₄ solution gave better results for the sensitivity of the substance to be analyzed compared to acetate buffer. The standard DPSV addition method was successfully applied to quantify Pb in hair dye samples, yielding values below 0.45% in Pb [40]. In analysis of tap water and groundwater samples, Pb was detected by differential pulse anodic voltammetry using a polypyrrole-modified glassy carbon electrode, Bi film and metal organic framework, and 0.5 M K₃[Fe(CN)₆] and 1 M KCl as the supporting electrolyte. The electrode gave a wide linear range (0.5 to 10 μg/L). It also showed remarkable resistance to interfering ions, repeatability, and stability [41]. Another technique used a bismuth film, Nafion, and a nitrogen-admixed worm carbon frame that modified a glassy carbon electrode (Nafion-WNCF/BFGCE). Under optimal experimental conditions, the modified glassy electrode exhibited a wide linear range from 0.5 mg/L to 100 mg/L. All results showed that the admixed worm carbon frame can be considered as a green and low-cost nanomaterial [42]. Recent advances in electrochemical sensing of lead ion are being summarized elsewhere [43].

1.5. Determination of Cd

The cadmium cation Cd²⁺ has been detected in a variety of samples, and one of them was rice. In this study, a glassy carbon electrode with poly-L-tyrosine and bismuth, with the shape of buds, was modified, and samples were studied with square pulse anodic stripping voltammetry. The preparation and testing of the membrane electrode composite showed good stability, repeatability, and anti-interference capability. It was successfully applied in the determination of Cd, with a solution of 5.0 mM KCl and 3.0 μM Bi³⁺ as the electrolyte, with satisfactory results according to those of the spectral method [44]. Two further studies were conducted to detect the Cd ion in water samples, with square pulse anodic voltammetry, acetate buffer, and a glassy carbon electrode. In a study, this electrode was modified with MnO₂, Bi₂O₃, and graphene oxide, giving a larger electrochemically active surface area and lower transportable charge resistance. This happened thanks to the strong synergistic effect between graphene oxide nanosheets and MnO₂/Bi₂O₃ microspheres. The technique showed good repeatability, reproducibility, and stability [45]. In the other technique, the glassy carbon electrode was modified with a metallic organic frame of iron with amine, with the sensor showing good recoveries [46]. A SWASV method using a loaded titanium dioxide nanotube array electrode showed high stability, reproducibility, and sensitivity and was accurate for Cd determination in water, soil, and tea samples [47].

Another voltammetric technique used for the detection of cadmium is linear sweep voltammetry (LSV). In this method, a glassy carbon electrode was modified with 1,2-di-[o-aminothiophenyl]ethane and analyzed in a 0.1 M LiClO₄ solution. A stable and well-controlled electrograft process thus developed, leading to a single-layer organic membrane [48].

Successful determination of cadmium with high sensitivity was also achieved by differential pulse voltammetry in seawater samples. The electrode used was a glassy carbon electrode formatted with nanoFe₃O₂, MoS₂, and Nafion, with simple operation, rapid response, and high sensitivity. The linear relationship of Cd concentration was found in the range of 5–300 μg/L. Recovery of Cd in seawater ranged from 99.2 to 102.9% [49]. A further determination of Cd in water samples (dam water, lake water, wastewater) was performed in a phosphate buffer, pH 5, by means of an organic metal frame and graphene oxide graphite rod electrode and using differential pulse anodic stripping voltammetry. This technique exhibited high stability, speed, and simplicity, good sensitivity, and high reproducibility [50].

The cadmium ion was also determined concomitantly with mercury cations in drinking water samples, with a graphite-modified glassy electrode containing Se and square pulse anodic stripping voltammetry. The electrode’s ability to absorb cadmium and mercury makes it suitable for water purification purposes [51].

1.6. Determination of Cu

Copper ions have been identified in drinking water samples, by square pulse anodic stripping voltammetry, with a selective ion Ca²⁺ electrode [52]. An amino acid containing organosilicate gel (3-mercaptopropyl)-trimethoxysilane gold electrode was used to determine Cu in tap and lake water samples. A solution of 0.1 M KCl, 2 mM [Fe(CN)₆]^3−/4− and 5 mM [Ru(NH₃)₆]³⁺ served as the supporting electrolyte. Analysis of real samples proved that this electrode was favorable as a transducer platform for Cu²⁺ detection [53].

Differential pulse voltammetry was also used to detect Cu in drinking water, specifically cathodic differential pulse voltammetry. The working electrode was a carbon paste electrode modified with a species of Mesorhizobium opportonistum bacteria that were first used in the production of a microbial biosensor, and the electrolyte was a 0.01 M HClO₄ solution. The microbial biosensor has advantages for the determination of Cu(II), including good sensitivity and reproducibility, easy preparation, low cost, applicability to the sample, and no need for additional chemical processes [54]. Another technique utilizing differential pulse anodic stripping voltammetry used a glassy electrode modified with Nafion solution, multiwalled carbon nanotubes, and 1-butyl-3-methylimidazole hexafluorophosphate. Cu was detected with a 0.1 M acetate and chlorate buffer in juice and tea drinks. The modified electrode has strong anti-pollution properties and has the advantages of disposable design, low cost, renewability, and excellent interference protection [55]. A pencil graphite electrode formatted with Cu²⁺ and cyclam (macrocyclic ligand, 1,4,8,11-tetraazacyclotetradecane) (Cu(II)-modified PGE) was also used to detect Cu ions by anodic stripping adsorption voltammetry. The supporting electrolyte was a 1 × 10⁻³ M CuSO₄, 1 M H₂SO₄ sulphate buffer. Cyclam chelate of a bifunctional ligand was shown to be highly Cu²⁺ selective compared to other divalent cations. The simplicity of preparation, the robustness of the covalent graft, the possible miniaturization of the system, the possibility of reusing the modified electrodes with one step ASV, the low risk of eutrophication, and the low reagent consumption make this process very attractive for field measurements in both fresh water and marine environments [56]. Copper ions were determined in different water samples using a magnetic carbon paste electrode, and for this purpose L-cysteine functionalized core–shell Fe₃O₄@Au nanoparticles. A phosphate buffer solution with pH 5.0 was used as the supporting electrolyte, and the results showed that the method has satisfactory reproducibility and a low detection limit of 0.4 nM [57]. Finally, a prion-derived copper(II)-binding peptide was assembled onto a gold electrode surface for a new voltammetric biosensor. The biosensor had excellent selectivity, even in the presence of Zn, Cd, Fe, or Ni ions, and was applicable in the agricultural field measuring seeds of Coffea arabica [58].

1.7. Determination of Zn

A boron impurity diamond electrode was used to determine Zn²⁺ ions in pharmaceutical samples, by square pulse anodic stripping voltammetry and batch injection in the analysis (BIA-SWASV). In this study, a simultaneous determination was performed for zinc (Zn) and ascorbic acid (AA). The proposed method exhibits high efficiency, sufficient selectivity, and good accuracy, while requiring minimal sample preparation as well as small amount of reagents and sample volumes in each analysis. It has better limits of detection and does not require the use of an additional reagent to avoid the interference of citrate (pharmaceutical excipient) in the determination of ions [59]. Table 1 summarizes the applications of voltammetry in the determination of heavy metals, mainly in water samples.

Table 1. Applications of voltammetric analysis for single heavy metals.

Metal	Technique	Electrode	Supporting Electrolyte	Type of Sample	Limit of Detection (LOD)	Ref.
Pb²⁺	ASV	Carbon electrode Cu-shaped (Cu-CE)	0.01 M HCl + 1 M KCl	Drinking water, sewage	1 μM	[27]
	ASV	Glassy carbon electrode formatted with eDAQ	1 M KNO₃	Tap water		[28]
	SWV	Carbon paste electrode modified with geopolymer cement	0.2 M NaNO₃	Tap, well, and thermal water	2.3 × 10⁻⁹ M	[29]
	SWASV	electrode printed with ink injection printer and formatted with multiwalled carbon nanotubes	0.1 M acetate buffer	Drinking water	1.0 μg/L	[30]
	SWASV	Lithographically printed electrode Bi formatted and hierarchically tubular and porous biochar	acetate buffer (0.1 M, pH 4.5) + 500 μg/L Bi³⁺	Water	0.02 μg/L	[31]
	SWASV	Lithographically printed electrode carbon modified with dopamine polymer and polypyrolle hydrogel	Acetate buffer (pH 4.5)	River water	0.15 μg/L	[32]
	SWASV	Glassy carbon electrode modified with Fe₃O₄ in a Schiff base network	10⁻¹ M ΚΝO₃	Food	0.95 nM	[33]
	SWASV	Graphene oxide electrode modified with Bi and N	0.1 M, pH 4.5 acetate buffer	Tap water	10.9 pM	[34]
	SWASV	Glassy carbon electrode modified with Bi and Bi₂O₃	0.1 M acetate buffer	Tap water, canal water, soil near a factory	6.3 nM	[35]
	SWASV	Glassy carbon electrode modified with two-dimensional MXene with blue color	0.01 Μ, phosphate buffer, pH 6.5	Bottled water, tap water, lake water	0.97 nM	[36]
	LSASV	Coal paste electrode modified with clay	0.1 M KCl	Water, biological water		[39]
	DPSV	Graphite-cork electrode	0.5 M H₂SO₄, 0.1 M, acetate buffer, pH 4.5	Hair dye	1.06 μΜ (0.5 M H₂SO₄), 1.26 μΜ (0.1 M acetate buffer, pH 4.5)	[40]
	DPASV	Glassy carbon electrode modified with polypyrolle, Bi film, and metal organic frame	0.5 mM K₃[Fe(CN)₆] + 1 M KCl	Tap water, groundwater sample	0.05 μg/L	[41]
	DPASV	Glassy carbon electrode modified with bismuth film, Nafion, and a worm-like carbon structure with nitrogen admixture	0.1 M acetate buffer, pH 4.5	Lake water, tap water	0.2 μg/L	[42]
	SWASV	rGO/MoS2/CS nanocomposite modified glassy carbon electrode	0.10 M acetate buffer	tobacco	0.0016 μM	[37]
	SWASV	Bismuth film-modified electrode	0.2 Μ acetate buffer solution	Soil		[38]
Cd²⁺	CV SWASV	loaded titanium dioxide nanotube array electrode	0.1 M acetate buffer	Soil and tea	0.01 μM	[47]
	SWASV	Glassy carbon electrode modified with poly-L-tyrosine and bismuth reminiscent of buds	5.0 mM KCl + 3.0 μM Bi³⁺	Rice	0.11 nΜ	[44]
	SWASV	Glassy carbon electrode modified with MnO₂, Bi₂O₃, and graphene oxide	0.1 M acetate buffer	Water	0.22 μg/L	[45]
	SWASV	Glassy carbon electrode modified with metal organic frame iron with amine	acetate buffer	Water	0.03 μΜ	[46]
	LSV	Glassy carbon electrode modified with 1,2-di-[o-aminothiophenyl	0.1 M LiClO₄	Real samples	1.7 μg/L	[48]
	DPV	Glassy carbon electrode modified with nano-Fe₃O₂, MoS₂, and Nafion	0.1 M acetate buffer, pH 4.2	Sea water	0.053 μg/L	[49]
	DPASV	Graphite rod electrode modified with organic metal frame and graphene oxide	0.1 Μ phosphate buffer, pH 5.0	River water, dam water, sewage	0.03 μg/L	[50]
	SWASV	Glassy carbon electrode modified with graphite containing Se	1 M phosphate buffer	Drinking water	1.9 μg/L, Hg: 4.3 μg/L	[51]
Cu²⁺	CV	prion-derived copper(II)-binding peptide aassembled onto a gold electrode	0.2 M phosphate buffer	Coffee arabica	8.0 × 10⁻⁸ M (5.1 μg L⁻¹)	[58]
	SWASV	Selective Ca²⁺ ion	0.1 M acetate buffer	Drinking water	1 μΜ	[52]
	SWV	Gold electrode with (3-mercaptopropyl)-trimethoxysilane modified with microfiber organosilicate gel containing amino acid	0.1 M KCl solution + 2 × 10⁻³ M [Fe(CN)₆]^3−/4− + 5 × 10⁻³ M [Ru(NH₃)₆]³⁺	Tap water, lake water	2.6 pM	[53]
	DPCSV	Carbon paste electrode modified with biosensor Mesorhizobium opportonistum	0.01M HClO₄	Drinking water	2.0 × 10⁻⁸ M	[54]
	DPASV	Glassy carbon electrode modified with Nafion solution, multiwalled carbon nanotubes, and 1-butyl-3-methylimidazole hexafluorophosphate	0.1 M acetate buffer + 0.1 M KCl	Juice and tea drinks	16 μg/L	[55]
	AdASV	Pencil graphite electrode formatted with Cu²⁺ and cyclam	1 × 10⁻³ M CuSO₄/1 M H₂SO₄	Sea water	16 nM	[56]
	DPV	Magnetic carbon paste electrode, L-cysteine functionalized core–shell	Phosphate buffer, pH 5.0	Water	0.4 nM	[57]
Zn²⁺	Batch Injection Analysis (BIA)-SWASV	Diamond electrode with boron admixture	Britton–Robinson (BR) 0.04 M	Pharmaceutical samples	0.2 μΜ	[59]

2. Applications of Voltammetric Analysis for Two Heavy Metals Simultaneously

Voltammetry has been used for two-heavy-metal determination in various samples, as described in Table 2 and in the following sections.

2.1. Simultaneous Determination of Pb and Cd

The simultaneous determination of the ions of the heavy metals lead and cadmium in a variety of samples, mainly water, is the most widespread, based on the literature. Square wave voltammetry (SWV) and differential pulse voltammetry (DPV) were also very helpful in this case, as they gave remarkable results, with low detection limits that are in line with the limits established by individual health assurance bodies.

One of the techniques for detecting these metals in coastal and transitional waters by anodic stripping voltammetry (ASV) involved the use of Hg film electrode (MFE) [60]. In natural brine samples, Pb and Cd were determined using a hanging Hg drop electrode (HMDE). The proposed procedure allowed the determination of Cd (0.001 μg/L) and Pb (0.005 μg/L) after only 100 times dilution, as samples, such as brine, with high salinity must be significantly diluted. LOQs were found below recommendations related to brine use in balneotherapy [61]. In another method, a copper film electrode (Cu-FE) was used, having as the electrolyte the solution of 0.1 M HCl and 0.4 M NaCl. The low limits of detection showed that Cu-based electrodes are a promising solution for Hg electrode replacement and for an environmentally friendly anodic voltammetry [62].

Square wave voltammetry (SWV) simultaneously detected Pb and Cd ions in water samples with a carbon paste electrode modified with Bi film. The supporting electrolyte was a 0.01 M acetate buffer at pH 4.6. The proposed method was accurate and sensitive. The resulting electrode is not toxic at all [63].

Square wave anodic stripping voltammetry has also been widely exploited, with one of the methods involving a lithographically printed graphite-based electrode covered with Nafion. A 50 mM NaCl solution at pH 4.6 served as an electrolyte. The graphite-based Nafion-coated electrodes were stored in different humidity and temperature conditions and analyzed using anodic square wave analytic voltammetry, cyclic voltammetry, electrochemical impedance spectroscopy, and scanning electron microscopy. The study of the different conditions was decisive in extracting results, as the morphological and conductive properties of Nafion thin films have a strong dependence on environmental conditions. Significant differences were observed in changing humidity conditions, with enhancement of the electrochemical performance of sensors at lower humidity [64]. Another technique involves the use of a carbon paste electrode modified with multiwalled carbon nanotubes and antimony trioxide. As an electrolyte, a 0.01 M HCl solution was used to detect Pb and Cd ions in water samples. The comparison of the new method with GFAAS (graphite furnace atomic absorption spectroscopy) in real samples revealed that the new SWASV method for the determination of Cd²⁺ and Pb²⁺ ions is free of systematic errors and offers low detection limits [65]. A lithographically printed black carbon electrode was also modified with poly(propyleneimine), creating a sensitive sensor with low limits of detection in the determination of Pb and Cd metals in water samples, amplified by the 0.1 M acetate buffer electrolyte and having pH 4.6 [66]. Glassy carbon electrodes have found wide application in the detection of the desired metals, giving good results in terms of sensitivity and selectivity. One of them was modified with nanocomposite reduced graphene oxide decorated with (BiO)₂CO₃ and Nafion and gave low detection limits in a 3 M KCl solution [67]. Another glassy carbon electrode was modified with polythionine (in the presence of Bi) and multiwalled carbon nanotubes with an acetate buffer. PTH improves detection limits. PTH is more sensitive to Pb²⁺, so in the presence of Bi³⁺, there can be a complementary effect [68]. To detect ions in seawater and tap water samples, a carbon glassy electrode with carbon combined with N and Ti₃C₂-MXene was modified. In a solution of 5 mM [Fe(CN)₆]^3−/4− and 0.10 M KCl, ions with low detection limits were found. The modified electrode was more sensitive to Pb²⁺ than to Cd²⁺ and showed excellent selectivity for these two ions in the presence of interfering ions and molecules [69]. Another technique involved the study of deep eutectic solvents for the microextraction of liquid-liquid reverse phase dispersion of lead and cadmium in vegetable oil samples, using an Hg-shaped electrode and a 0.1 M HCl solution as the supporting electrolyte [70]. For the detection of Pb and Cd ions with a high linear range, sensitivity, and stability, a nanoporous Bi glassy carbon electrode was modified, which was superficially decorated with Bi₂O₃. After coating an amorphous layer of Bi₂O₃ on the surface of NPBi, the results were satisfactory [71]. In samples of rice water, raw milk, and tobacco extract, Pb and Cd ions with low detection limits were found using a 0.1 M acetate buffer solution and an electrode modified with salicylidene-2-amino benzyl alcohol and multiwalled carbon nanotubes. This technique showed good conductivity and fast electron transfer [72]. One method of determining the desired ions in wastewater utilized a lithographically printed electrode, which was shaped with Nafion. A 0.1 M acetate buffer served as an electrolyte carrier. The proposed electrode showed greater affinity for Pb²⁺ ions due to the presence of ligand-SO₃²⁻ on the electrode surface, as was demonstrated by the maintained peak of Pb²⁺ intensity [73].

Differential pulse anodic stripping voltammetry (DPASV) is one of the most applied electroanalytical techniques for the detection of heavy metals and specifically for the ions of the metals Pb and Cd. Certified estuarine water samples were combined with a lithographically printed two-dimensional carbon electrode shaped with bismuthene. The use of 2D Biexf-SPCE for the detection of Pb²⁺ and Cd²⁺ ions yielded low LOD limits and LOQ, high sensitivities, as well as good repeatability and reproducibility [74]. Another recent technique involves a modified glassy carbon electrode with silane bentonite decorated with Ag nanoparticles. The electrode, with the help of the supporting electrolyte (acetate buffer 0.1 M, pH 4.5), gave low detection limits. Its stability was proved by repeated measurements. The presence of several interference ions did not affect the detection of the two ions, although the presence of Zn²⁺ showed well-separated oxidative peaks [75]. A glassy carbon electrode was also modified with polyrutin and Ag nanoparticles for the simultaneous determination of Pb and Cd metals in water, soil, and wool samples. With polyrutin/AgNPs/GCE, experimental parameters such as the supporting electrolyte, ambient pH, deposition potential, and preconcentration time were studied [76].

In natural water samples, the two metals were also detected simultaneously and individually. The working electrode was a pencil graphite electrode formatted with polypyrrole and CO, while 0.1 M acetate buffer was used as the supporting electrolyte. A glassy carbon electrode formatted with Sb and Bi gave good results in terms of sensitivity and low detection limits of the metals Pb and Cd. The preparation of the modified electrode was quite simple and less time consuming [77]. A similar technique involved a glassy carbon electrode modified with Nafion and Bi nanoplates as well as a 0.1 M acetate buffer (pH 4.5) as an electrolyte. The Nafion/BiNP/GCE electrochemical sensors successfully detected Cd²⁺ and Pb²⁺ in tap water and wastewater, despite the presence of inhibitors in both samples [78]. A lithographically printed two-dimensional microfiber electrode formatted with Sb was used in the successful simultaneous detection of metals and gave satisfactory limits of detection as well as good reproducibility and accuracy. A solution of HCl 0.01 M and pH 2 was used as the supporting electrolyte. The excellent analytical effect of the electrode is due to the synergistic effect of the properties of both used nanomaterials [79]. Another technique involved a rotating disc glassy carbon electrode, which was also modified with Sb and a 0.01 M HCl solution. In situ preparation of the modified electrode is an effective strategy for improving the performance of the commonly used GC electrode [80].

In rice, honey, and vegetable samples, the ions of the metals Pb and Cd were detected simultaneously and successfully by forming a glassy carbon electrode, modified with carbon black and polyriboflavin in the presence of Bi. RF electropolymerization performed at the surface of the modified electrode played a complementary role with Bi³⁺ for the selective determination of Pb²⁺ and Cd²⁺. Specifically, PRF is more sensitive to Pb²⁺, while Bi³⁺ is more sensitive to Cd²⁺ [81]. For the determination of these metals in samples of charcoal from coffee tree bark, differential pulse adsorptive stripping voltammetry (DPAdSV) was applied with a charcoal-modified carbon paste electrode. The metals were successfully detected in a supporting electrolyte of 0.1 M acetate and a pH of 4.8. Some of the advantages of this new sensor are the use of environmental pollutants (coffee husks) for electrode forming, “zero cost”, and green production, as well as its very simple preparation [82]. Soil samples were analyzed with a glassy carbon electrode modified with Bi, with voltammetry SWASV, in 0.2 M acetate buffer, at pH 5 [83]. Pb and Cd ions were also simultaneously detected in environmental waters using a glassy carbon electrode coated with poly(amidoamine) dendrimer functionalized magnetic graphene oxide, with SWASV. This technique showed satisfactory results, with low detection limits, high sensitivity, and good anti-interference capability [84]. In soil samples, a bismuth film-modified glassy carbon electrode with SWASV was efficient for the simultaneous detection Pb and Cd ions [85,86,87,88].

2.2. Simultaneous Determination of Pb and Cu

In wine samples, ions of the metals Pb and Cu were determined simultaneously by anodic stripping voltammetry. A glassy carbon electrode was modified with Nafion and MnCo₂O₄ and in HCl/KCl buffer (0.1 mol/dm³), and the metals Pb and Cu were detected with low limits of detection and quantification. Under appropriate conditions, calibration curves were linear in the range 0.01–8 and 0.01–5 mg/dm³ for Pb and Cu, respectively, and the effects of sample dilution, pre-concentration time, and potential were optimized [89]. In another work, a hydroxyapatite (Hap/CE) shaped carbon electrode was constructed to detect Pb and Cu in water samples, with a solution of 1 M KNO₃ as the supporting electrolyte. While the sensitivity to detect copper pollution was sufficient, it was not satisfactory for lead as specified by the United States Environmental Protection Agency. The 92% w/w hydroxyapatite composite, which showed a ratio of approximately 1:1 between the exposed region of hydroxyapatite and carbon (by the Brunauer-Emmett–Teller method), showed a mean maximum redissolving oxidation intensity of approximately 250 μA/cm² and 150 μA/cm² for a 50 μM Pb²⁺ and Cu²⁺ solution, respectively [90]. For the determination of Pb and Cu ions in lake water samples, a glassy carbon electrode was modified with multiwalled carbon nanotubes, Nafion, and ZIF-67. The analysis was performed with a square pulse stripping voltammetry and an electrolyte of 0.1 M acetate buffer at pH 2.0. This electrode gave a wide linear range, good sensitivity, repeatability, reproducibility, anti-interference capability, stability, specificity, and applicability to real samples [91]. Another technique involves the use of a graphite electrode modified with caffeic acid in samples of artisanal sugar cane distillate, with a solution of 1 M HNO₃. The acidic medium produced an excellent polymer film that served in the simultaneous detection of metals. Excellent linear range, repeatability, reproducibility, and recovery were observed for the two metals Pb and Cu [92]. Finally, simultaneous detection of the two metals was also studied in plant species, as the Brassicaceae family is known to hyperaccumulate metals. For instance, SWASV using a glassy carbon electrode modified with mercury film was used for Pb and Cu determination on Lunaria annua L. [93].

2.3. Simultaneous Determination of Cd and Cu

For the simultaneous determination of the ions of the metals Cd and Cu, an electrode was modified with a poly(butylene-terephthalate adipate) copolymer and carbon nitrite dots as well as a phosphate buffer 0.1 M, pH 3.0, as the supporting electrolyte. The method presented excellent electrochemical activity, showing low limits of LOD and LOQ. A linear behavior in the concentration range of 0.1 to 1.0 mM for Cd and Cu showed excellent sensitivity [94]. The simultaneous determination of Cd and Cu has been applied in water, soil, and plant samples [95].

2.4. Simultaneous Determination of Cu and As

Τhe simultaneous determination of copper and arsenic in water samples is vital to guarantee environmental and public health, in agreement with regulations, and understanding the complex interactions between different contaminants in water systems.

The simultaneous detection of Cu²⁺ and As³⁺ ions was performed by square pulse anodic voltammetry using a gold nanostar electrode (AuNS-CSPE). A Britton–Robinson buffer solution was used as an electrolyte for this analysis, and the results showed that this method provides excellent accuracy compared to GF-AAS in river water and tap water samples [96]. Another technique involves a selective, stable, and reproducible glassy carbon electrode modified with a new polymethyldopa-based nanocomposite along with gold nanoparticles immobilized on the surface of magnetic graphene oxide. The electrolyte used was a buffer solution of acetates (0.1 M, pH 6) and KCl 0.1 M. LOD levels were below acceptable limits and were equal to 0.11 μg/L and 0.15 μg/L for Cu and As, respectively [97].

2.5. Simultaneous Determination of Cu and Hg

Simultaneous determination of Cu and Hg has been applied in fruit, herbal, and vegetable samples, such as tea, spinach, tomato, and apple samples, using SWASV with a gold electrode (GE). This method is valid, with good selectivity and sensitivity, even in complex matrices [98].

Table 2. Applications of voltammetric analysis for two heavy metals simultaneously.

Metals	Technique	Electrode	Supporting Electrolyte	Type of Sample	Limit of Detection (LOD)	Ref.
Pb²⁺, Cd²⁺	ASV	Hg film electrode		Coastal and transitional waters	4.0 ng/L, 0.50 ng/L	[60]
	ASV	Hanging Hg drop electrode	9.00 mL model brine	Brine		[61]
	ASV	Cu film electrode	0.1 M HCl + 0.4 M NaCl	Tap water	0.6 μg/L, 1.8 μg/L	[62]
	SWV	Carbon paste electrode modified with Bi film	0.01 Μ, acetate buffer, pH 4.6	Water	0.3 μg/L, 0.5 μg/L	[63]
	SWASV	Lithographically printed electrode based on graphite and covered with Nafion	acetate buffer 50 mM + NaCl 50 mM, pH 4.6	Spring water, sea water		[64]
	SWASV	Carbon paste electrode modified from multiwalled carbon nanotubes and antimony trioxide	0.01 M HCl	Tap water	1.2 μg/L, 1.7 μg/L	[65]
	SWASV	Lithographically printed black carbon electrode with poly(propyleneimine)	acetate buffer 0.1 M, pH 4.6	Tap water	3.6 μg/L, 15.3 μg/L	[66]
	SWASV	Glassy carbon electrode modified with a reduced graphene oxide nanocomposite decorated with (BiO)₂CO₃ and Nafion	3 M KCl	Water	0.24 µg/L, 0.16 µg/L	[67]
	SWASV	Polythionine-modified glassy carbon electrode (in the presence of Bi) and multiwall carbon nanotubes	0.1 M, acetate buffer, pH 3.5	Water	0.4 nM, 0.6 nM	[68]
	SWASV	Glassy carbon electrode modified with carbon combined with N, and Ti₃C₂-ΜΧene	5 mM [Fe(CN)₆]^3−/4− solution + 0.10 M KCl	Sea water, tap water	1.10 nM, 2.55 nM	[69]
	SWASV	Carbon electrode modified with Hg	0.1 M HCl	Vegetable oil	0.01 µg/kg, 0.06 µg/kg	[70]
	SWASV	Glassy carbon electrode modified with nanoporous Bi, superficially decorated with Bi₂O₃	0.1 M, acetate buffer, pH 3.0–5.5,	Tap water	0.02 µg/L, 0.03 µg/L	[71]
	SWASV	electrode modified with salicylidene-2-amino benzyl alcohol and multiwalled carbon nanotubes	0.1 M acetate buffer	Rice water, tobacco extract, raw milk	0.012 ng/L, 0.02 ng/L	[72]
	SWASV	Lithographically printed electrode formatted with Nafion	0.1 M acetate buffer	Sewage	8.4 μg/L, 0.032 mg/L	[73]
	DPASV	Lithographically printed electrode bismuthene-modified two-dimensional carbon	0.1 M acetate buffer, pH 4.5	Certified estuarine water samples	0.06 μg/L, 0.07 μg/L	[74]
	DPASV	Glassy carbon electrode modified with silane bentonite decorated with Ag nanoparticles	acetate buffer, pH 4.0	River water	0.88 µg/L, 0.79 µg/L	[75]
	DPASV	Glassy carbon electrode modified with polyrutin and Ag nanoparticles	0.1 M, acetate buffer, pH 5	Tap water, soil sample, hair	3 nM, 10 nM	[76]
	DPASV	Polypyrol-modified pencil graphite electrode and CO₂	0.1 M acetate buffer	Natural water	0.018 nM, 0.023 nM	[99]
	DPASV	Glassy carbon electrode modified with Sb and Bi	0.1 M acetate buffer, pH 4.5	CRM soil sample, tap water	0.01 μg/L, 0.5 μg/L	[77]
	DPASV	Glassy carbon electrode modified with Nafion and Bi nanoplates	0.1 M acetate buffer, pH 4.5	Tap water, sewage	0.178 nM, 0.376 nM	[78]
	DPASV	Lithographically printed electrode two-dimensional microfiber modified with Sb	0.01 M HCl, pH 2	Certified estuarine water	0.1 µg/L, 0.9 μg/L	[79]
	DPSV	Glassy carbon electrode rotating disc modified with Sb	0.01 M HCl	Soil water, soil	1.1 μg/L, 1.4 μg/L	[80]
	DPASV	Glassy carbon electrode modified with carbon black and polyriboflavin in the presence of Bi	0.1 M, acetate buffer, pH 5	Rice, honey, vegetables	0.13 nM, 0.16 nM	[81]
	DPAdSV	Carbon paste electrode modified with charcoal	0.1 M, acetate buffer, pH 4.8	Samples of biochar (charcoal) from coffee tree husks	0.2 µg/L, 1.7 µg/L	[82]
	SWASV	Glassy carbon electrode modified with Bi	0.2 M, acetate buffer, pH 5	Soil		[83]
	SWASV	Glassy carbon electrode coated with poly(amidoamine) dendrimer-functionalized magnetic graphene oxide	0.1 M acetate buffer	Water	130 ng/L, 70 ng/L	[84]
	SWASV	in situ electroplating bismuth film-modified glassy carbon electrode	0.2 M acetate buffer	Soil		[88]
	SWASV	electrode made of glass carbon modified by bismuth film	0.2 M acetate buffer	Soil		[86,87]
	SWASV	bismuth film-modified glassy carbon electrode	Acetate buffer	Soil		[85]
Cd²⁺, Cu²⁺	SWV	electrode modified with poly(butylene-terephthalate adipate) copolymer and carbon nitrite dots	0.1 M phosphate buffer, pH 3.0	Tap water	2.7 μM (Cd), 7.09 μΜ (Cu)	[94]
Cd²⁺, Cu²⁺	CSV			Groundwater, soil, and Alhagi maurorum plants	0.011 ng/mL (Cu²⁺) 0.013 ng/mL (Cd²⁺)	[95]
Cu²⁺, As³⁺	SWASV	Nanostar gold electrode	Britton–Robinson buffer	River water, tap water	42.5 μg/L, 2.9 μg/L	[96]
Cu²⁺, As³⁺	SWASV	Glassy carbon electrode with a new polymethyldopa-based nanocomposite material together with gold nanoparticles immobilized on the surface of magnetic graphene oxide	0.1 M acetate buffer + 0.1 M KCl, (pH 6.0)	Drinking water, pool water	0.11 μg/L, 0.15 μg/L	[97]
Cu²⁺, Hg²⁺	SWASV	gold electrode (GE)		Tea, Spinach, Tomato, Apple		[98]

3. Applications of Voltammetric Analysis for Three or More Heavy Metals Simultaneously

Voltammetry has been used for determination of three or more heavy metals in various samples, as described in Table 3 and in the following sections.

3.1. Simultaneous Determination of Cu, Mn, and Zn

Cu, Mn, and Zn are important micronutrients in soil. Their simultaneous determination has been achieved by differential pulse stripping voltammetry (DPSV) and square wave stripping voltammetry (SWSV) with a pencil graphite electrode in soil samples [100].

3.2. Simultaneous Determination of Pb, Cd, and Hg

Simultaneous determination of Pb, Cd, and Hg was performed in water samples, utilizing anodic voltammetry. The electrode was a 3D-printed graphene and polylactic acid electrode and as an electrolyte a 1 mM solution of Ferrocenemethanol was used. Hg was easily measured at trace levels in unformatted graphene/Polylactic acid, but Pb and Cd required Bi microparticles to reach the required detection limits [101]. By differential pulse stripping voltammetry, metals were determined in samples of liquid foods, namely orange juice, apple juice, and cow’s milk. A nanoelectrode was modified with Au, and the results gave low detection and quantification limits. The mobile phone-based electrochemical platform enabled sensitive and affordable monitoring of heavy metals in popular liquid foods, with minimized requirements for laboratory instruments and technical expertise [102]. With the same electroanalytical technique, metals were detected in tap and river water samples in a 0.1 M HCl solution. A carbon paste electrode with Na₂CO₃ and active Hordeum vulgare L. powder was used as the working electrode [103].

3.3. Simultaneous Determination of Pb, Cd, and Cu

In the analysis of the determination of the three metals Pb, Cd, and Cu, a carbon paste electrode modified with a shell core of Bigarreau Burlat, one of the most widespread cherry varieties, was used with square wave voltammetry. A 0.2 M acetate buffer was used as the supporting electrolyte. The electrode showed stability and selectivity in detecting these metals in seawater, tap water, and industrial wastewater samples. The modified electrode can be applied as an environmentally friendly and low-cost electrochemical sensor [104]. Square-pulse stripping voltammetry simultaneously detected the cations of these metals in water samples, with a microelectrode modified with high-density carbon nanotube fiber rods. The technique exhibited exceptional sensitivity and detection limits well below those set by the EPA and WHO [105]. Another technique involved the use of gel-embedded antifouling microelectrode arrays for the simultaneous detection of Pb, Cd, and Cu. An innovative underwater detector (TracMetal) was used, with surface water sampling to quantify the targeted trace metals in the dissolved fractions <0.2 μm and <0.02 μm of suspended particulate matter using phytoplankton nets at the mouth of an estuary [106]. A glassy carbon electrode was modified with Fe₃O₄ and D-valine for the simultaneous determination of Pb, Cd, and Cu metals in water samples, using 0.1 M acetate buffer [107]. For the same purpose, a sensitive glassy carbon electrode was also modified and shaped by the ZnO and Nafion nanostructure. A solution of 0.1 M KCl and 5 mM [Ru(NH₃)₆]₃ was used, and measurements showed that the working electrode is a sensitive electrode, with good electrochemical characteristics and efficient analytical parameters for the detection of heavy metals [108].

Differential pulse voltammetry has also found application in the simultaneous detection of metals Pb, Cd, and Cu. One technique used a hanging Hg drop electrode (HDME) in combination with magnetic Fe₃O₄@SiO₂-cyclene nanoparticles, with a 0.5 M KCl solution at pH 6.0. Magnetic Fe₃O₄@SiO₂-cyclene nanoparticles were developed and used as an adsorbent for Pb, Cd, and Cu but also as a means to eliminate ions of these metals from individual and mixed solutions by titrating nanocomposites on suspension. The smallest number of nanoparticles was needed to bind Cu²⁺ [109]. In agricultural irrigation water samples, the three metals were detected simultaneously with a boron-sensitive biocarbon electrode. In a 0.1 M acetate buffer, this electrode had high conductivity and excellent electrocatalytic action for the simultaneous electroanalysis of metals [110].

3.4. Simultaneous Determination of Pb, Cd, and Zn

Cations of the heavy metals lead, cadmium, and zinc were detected in fish feed by anodic voltammetry. The electrode was an electrochemical fluid injection-modified granule, consisting of three conductive polymer electrodes loaded with carbon fibers embedded in a plastic liquid support, while a 0.1 M acetate buffer served as the supporting electrolyte. The experimental variables (concentration of bismuth plating solution, deposition potential, sample volume, and stripping method) were investigated, and possible interference was evaluated [111]. To determine the specific metals in water samples, a square pulse anodic voltammetry was used, and a pencil graphite electrode modified with multiwalled and Bi carbon nanotubes was constructed. This technique proved easy, selective, and highly sensitive, as it was combined with a low-cost effective graphite electrode [112]. With the same voltammetric method, these metals were simultaneously detected using a lithographically printed carbon electrode modified with poly(3,4-ethylenedioxythiophene) fibers with aqueous polyvinyl alcohol solution and Ag nanoparticles. AgNPs can increase the conductivity of composite fibers and act as nucleation sites for Zn deposition, resulting in increased sensitivity of Zn detection. In a 0.1 M acetate buffer and at pH 4.6, Pb metal cations were successfully detected in drinking water samples [113]. Another technique studied samples of pasteurized milk, apple juice, and drinking water with a carbon paste electrode modified with CuO and TbFeO₃ in acetate buffer at pH 4.8. The electrode had high detection capabilities for lead, cadmium, and zinc in water and food samples. In addition, it was affordable and environmentally friendly [114]. In a recent study to detect metals in water samples, a carbon paste electrode was modified with Bi and Sb [115].

3.5. Simultaneous Determination of Pb, Cu, and Zn

In water samples, ions of the metals Pb, Cu and Zn were simultaneously detected with the help of anodic stripping square wave voltammetry. Multi-wall composite carbon nanotubes from polyaniline gold nanoparticles were used as electrochemical sensors and a 0.1 M acetate buffer with pH 5 as a supporting electrolyte. The method showed highly analytical characteristics as the LOD limits of the three ions were significantly below the guidelines set by the EPA [116].

3.6. Simultaneous Determination of Cd, Cu, and Zn

A lithographically printed carbon electrode was modified with polyethylenimide, graphene oxide, and graphite for the simultaneous detection of ions of the metals Cd, Cu, and Zn by square pulse anodic stripping voltammetry. A buffer solution of 0.25 M acetate at pH 4.5 was used as a supporting electrolyte. According to the results, the proposed method showed sufficient LOD, sensitivity, selectivity, and reproducibility for the detection of these metals in water samples [117].

3.7. Simultaneous Determination of Cd, Cu, and Hg

SWASV, along with ligand-coated magnetite nanoparticles, was applied in the surface modification of a carbon paste electrode, which was characterized for its simplicity, sensitivity, and selectivity for simultaneous determination of Cd, Cu, and Hg in water and foodstuff samples such as tobacco, carrot, rice, fish, and shrimp [118,119].

3.8. Simultaneous Determination of Pb, Cd, Cu, and Hg

A lithographically printed carbon electrode was modified with Ag nanoparticles (AgNS/SPCE) to simultaneously determine the metals Pb, Cd, Cu, and Hg in tap water, rainwater, and lake samples. Due to the excellent electrical conductivity and high electrocatalytic activity of AgNS, two distinct upward signals were recorded for Cd and Pb in the AgNS/SPC electrode. LOD levels were below the permissible limits [120]. In milk samples, the metals Pb, Cd, Cu, and Hg were also detected simultaneously by means of a glassy carbon electrode magnetite modified with Fe₃O₄ and silica, in a buffer solution of 0.1 M acetate at pH 5. The method proved economical, sensitive, and simple [121]. DPASV with fullerene-chitosan-modified GCE was also used for the determination of these metals in tap water, milk, and honey samples and showed excellent performance, good reproducibility, and suitability for long-term usage [122].

3.9. Simultaneous Determination of Pb, Cd, Cu, and Zn

Some papers deal with the simultaneous identification of all four heavy metals of interest. For this purpose, a lithographically printed carbon electrode with Bi and Hg (Bi/Hg-SPCE) was formatted with 0.1 M acetate buffer and pH 4.5 in water samples. The sensor was disposable and showed the advantages of in situ measurements, low cost, simple construction, and multiple measurement capability. It also gave a wide cathode window, good electrochemical activity, and high sensitivity for simultaneous analyte detection [122]. A pencil graphite electrode modified with multiwalled carbon nanotubes, Na-montmorilonite, and Bi-nanoparticles (BiNP/MWCNT-NNaM/PGE) helped to detect the four heavy metals simultaneously, with a 0.1 M acetate buffer at pH 4.5 as the supporting electrolyte. The electrode gave a wide linear range. The structural and electrochemical characterizations of the BiNP/MWCNT-NNaM/PGE nanocomposite demonstrate a large surface area and low interfacial tension [123]. Simultaneous determination of Pb, Cd, Cu, and Zn was applied in soil samples using ASV with a glassy carbon working electrode (GCE with Bi(III) as the substrate of the GCE electrode), constituting a cheap and fast method enabling the determination of these metals in the concentrations that occur in Mediterranean soils [17]. Pencil graphite electrode modified with multiwalled carbon nanotubes, Na-montmorilonite, and Bi nanoparticles was applied in the simultaneous determination of Pb, Cd, Cu, and Zn in tap water [124].

3.10. Simultaneous Determination of Pb and Other Heavy Metals

The lead cation has been detected along with some other metals in addition to those mentioned above, such as mercury (Hg), tellurium (Tl), cobalt (Co), and antimony (Sb).

In the simultaneous determination of Pb and Hg, techniques have been developed that utilize square pulse anodic stripping. In one of these, a glassy carbon electrode modified with a Schiff base network was used as a working electrode and a 0.1 M KNO₃ and 0.01 M HCl solution was used as an electrolyte. The proposed sensor provided the advantages of simplicity, speed, and low cost for the determination of metals in edible samples [125]. In soil and lake water samples, metals from an electrode shaped with multiwalled carbon nanotubes and N,N′-di(salicylaldehyde)-1,2-diaminobenzene (BSD) (BSD/MWCNTs) were detected in a 0.1 M NaNO₃ solution. This technique exhibited high sensitivity, stability, and reproducibility [126].

In different water samples (tap water, mineral water, wastewater), Pb ions were detected with the help of a glassy carbon electrode modified with Bi nanoparticles and a dopamine polymer in multiwalled carbon nanotubes. This electrode gave a wide range of concentrations, a low detection limit (0.07 μg/L), and good selectivity. The most important advantage of the proposed sensor is the modern detection of Tl⁺ and Pb²⁺ in the presence of any heavy metals [127].

In drinking water samples, the simultaneous detection of ions of metals Pb, Cu, and Co was performed. This electrochemical analysis was performed using an Ethylenediaminetetraacetic acid-shaped carbon paste electrode with a square wave voltammetry. The technique is simple, fast, and inexpensive. The electrode was shown to be linear in the concentration range from 0.302 mM to 1.812 mM for Pb under optimal chemical and electrochemical conditions [128].

A 3D-printed electrode modified with polylactic acid with a graphene admixture was built to simultaneously detect traces of Pb and Sb metals in gunshot (GSR) samples. The proposed sensor showed stable and repeated responses in different ratios of analyzers, good selectivity, and high sensitivity. Furthermore, this work shows that this sampling and detection approach using the 3D-printed G-Polylactic acid platform can be combined with a 3D-printed electrochemical cell and a portable potentiostat to serve forensic police experts [129].

Table 3. Applications of voltammetric analysis of three and more heavy metals simultaneously.

Metal	Technique	Electrode	Supporting Electrolyte	Type of Sample	Limit of Detection (LOD)	Ref.
Pb²⁺, Cd²⁺, Hg²⁺	DPASV	carbon fiber electrode	0.01 M acetate buffer	Plant Soil	2.10, 0.93, 1.85 µg/L Cd, Pb, Hg	[130]
	ASV	3D-printed electrode graphene/polylactic acid	1 mM Ferrocenemethanol + 0.5 M KCl	Tap water	Hg: 6.1 nM	[101]
	DPSV	Nanoel Modified with Au		Liquid foods (cow’s milk, orange juice, apple juice)	1.0 μg/L, 1.1 μg/L, 1.2 μg/L	[102]
	DPASV	Carbon paste electrode modified with Na₂CO₃ and active Hordeum vulgare L. powder	0.1 M HCl	River water, tap water	0.0691 nM, 1.82 nM, 0.237 nM	[103]
Pb²⁺, Cd²⁺, Cu²⁺	SWV	Carbon paste electrode modified with Bigarreau Burlat shell core	acetate buffer (0.2 M)	Tap water, sea water, industrial wastewater	8.48 μg/L, 9.56 μg/L, 9.77 μg/L	[104]
	SWSV	Microgel modified with high-density carbon nanotube fiber rods		Tap water	−0.45 nM (92 ng/L), 0.26 nM (55 ng/L) in simulated drinking water −0.24 nM (27 ng/L) in tap water, 0.25 nM (28 ng/L) in simulated drinking water −6.0 nM, (376 ng/L) in tap water, 0.32 nM (20 ng/L) in simulated drinking water	[105]
	SWASV	Antifouling microelectrode arrays integrated in gel			1 ng/L, 0.7 ng/L, 6.6 ng/L	[106]
	SWASV	Glassy carbon electrode modified with Fe₃O₄ and D-valine	0.1 M acetate buffer	Water	18.89 nM, 18.38 nM, 7.481 nM	[107]
	SWASV	Glassy carbon electrode modified with nanostructure ZnO and Nafion	0.1 M KCl + 5.10⁻³ M [Ru(NH₃)₆]₃	Water	11.88 nM, 16.21 nM, 47.33 nM	[108]
	DPASV	Hanging Drop Hg electrode (HDME)	KCl 0.5 M, pH 6.0	Water		[109]
	DPASV	Biochar electrode in a metal form modified with B	0.1 M acetate buffer	Rural irrigation water	4 nM, 54 nM, 24 nM	[110]
Pb²⁺, Cd²⁺, Cu²⁺, Hg²⁺	DPASV	fullerene-chitosan-modified glassy carbon electrode	0.1 M acetate buffer	Tap water, Milk, Honey	3 nM (0.6 ppb), 14 nM (0.9 ppb), 1 nM (0.2 ppb) and 21 nM Hg, Cu, Pb, and Cd	[123]
	DPASV	Lithographically printed electrode carbon modified with Ag nanoparticles	1 M, acetate buffer, pH 4.4	Tap water, rainwater, lake water	2.5 μg/L, 0.4 μg/L, 0.73 μg/L, 0.7 μg/L	[120]
	DPSV	Magnetic glassy carbon electrode modified with Fe₃O₄ and silica	1 M acetate buffer, pH 5	Milk	16.5 nM, 56.1 nM, 79.4 nM, 56.7 nM	[121]
Pb²⁺, Cd²⁺, Zn²⁺	ASV	Polymeric electrode loaded with carbon fiber embedded in plastic fluid base	0.10 M acetate buffer	Fish feed		[111]
	SWASV	Pencil graphite electrode modified with multiwalled carbon nanotubes and Bi	acetate buffer, pH 4.5	Water	0.27 μg/L, 0.43 μg/L, 1.63 μg/L	[112]
	SWASV	Lithographically printed carbon electrode modified with poly(3,4-ethylenedioxythiophene) fibers with polyvinyl alcohol aqueous solution and Ag nanoparticles	0.1 M acetate buffer, pH 4.6	Drinking water	8 μg/L, 3 μg/L, 6 μg/L	[113]
	SWASV	Carbon paste electrode modified with CuO and TbFeO₃	acetate buffer, pH 4.8	Pasteurized milk, apple juice, drinking water	0.12 mg/L, 0.29 mg/L, 0.48 mg/L	[114]
	SWASV	Carbon paste electrode modified with Bi and Sb	acetate buffer, pH 5.6	Water	0.29 mg/L, 0.27 mg/L, 1.46 mg/L	[115]
Pb²⁺, Cu²⁺, Zn²⁺	SWASV	multiwalled Composite Carbon Nanotubes from Gold Nanoparticles with Polyaniline	0.1 M acetate buffer, pH 5.0	Water	0.037 μg/L, 0.017 μg/L, 0.039 μg/L	[116]
Pb²⁺, Cd²⁺, Cu²⁺, Zn²⁺	SWASV	hanging mercury drop electrode (HMDE)	0.01 Μ⁻¹ EDTA-Na₂ + 0.15 Μ NaCl + 0.5 Μ HCl	Tea, Spinach Tomato, Apple		[98]
	ASV	glassy carbon modified with Bi(III)	0.1 M acetate buffer	Soil	0.91 mg/kg (Zn), 0.88 mg/kg (Cd), 1.1 mg/kg (Cu), 0.88 mg/kg (Pb)	[17]
	SWASV	Lithographically printed electrode carbon modified Bi and Hg	1.0 M acetate buffer, pH 4.5	Surface water	0.082 μg/L, 0.16 μg/L, 0.64 μg/L, 0.97 μg/L	[123]
	SWASV	Pencil graphite electrode modified with multiwalled carbon nanotubes, Na-montmorilonite, and Bi nanoparticles	0.1 M acetate buffer, pH 4.5	Tap water	0.008 μΜ, 0.097 μΜ, 0.157 μΜ, 0.707 µM	[124]
Pb²⁺ and other metals	SWV	Glassy carbon electrode modified with Schiff base network	0.1 M KNO₃ + 0.01 M HCl	Edible samples	0.00072 μΜ	[125]
	SWASV	electrode modified with multiwalled carbon nanotubes and N,N′-di(salicylaldehyde)-1,2-diaminobenzene	0.1 M NaNO₃	Lake water, soil sample	0.3 nM	[126]
	SWASV	Glassy carbon electrode modified with Bi nanoparticles and dopamine polymer in multiwalled carbon nanotubes	0.1 M acetate buffer, pH 5	Tap water, mineral water, sewage	0.07 μg/L, Tl⁺: 0.04 μg/L	[127]
	SWV	Carbon paste electrode modified with Ethylenediaminetetraacetic acid	0.1 M NaCl	Drinking water	2.33 nM	[128]
	SWASV	3D-printed electrode using polylactic acid with graphene admixture	0.01 M HCl	Gunshot samples (GSR)	0.5 μg/L	[129]
Cd²⁺, Cu²⁺, Zn²⁺	SWASV	Lithographically printed electrode carbon modified with polyethyleneimide, graphene oxide, and graphite	0.25 M acetate buffer, pH 4.5	Water	0.53 μg/L, 1.52 μg/L, 0.23 μg/L	[117]
Cd²⁺, Cu²⁺, Hg²⁺	SWASV	Ligand-coated magnetite nanoparticle carbon paste electrode	B–R buffer	Water, Tobacco, Carrot, Rice, Fish, Shrimp	0.3, 0.1, 0.05 ng/mL for Cd²⁺, Cu²⁺, Hg²⁺	[118,119]
Cu²⁺, Zn²⁺, Mn²⁺	DPSV and SWSV	pencil graphite electrode	0.01 M acetate buffer	Soil	0.01 mg/L (Cu²⁺), 0.02 mg/L (Zn²⁺), 0.25 mg/L (Mn²⁺)	[100]

4. Conclusions

A literature review was performed regarding the determination of heavy metals, mainly in water, soil, and plant samples. Voltammetric techniques are fast, simple to apply, have low cost, and provide great repeatability, sensitivity, and selectivity. The most common techniques used to determine heavy metals are differential pulse voltammetry (DPV), square wave voltammetry (SWV), and anodic stripping voltammetry (ASV), and modified carbon paste and glassy carbon are the most common electrodes. The application of voltammetric techniques in the determination of heavy metals is an issue of great importance, while the developed analytical methods have shown selectivity and low detection limits. Electrochemical techniques offer an important advantage in heavy metal analysis, and the development of new and selective electrode surfaces and electrochemical detectors will enhance analytical figures of merit.

The simplicity of usage of certain materials, including bismuth film and nanoparticles, has been noted by researchers. The choice of appropriate materials for electrode modification is crucial because it enhances the electrode’s electrochemical characteristics, expands its effective surface area for the transfer of the electrochemical signal, and generates detectable signals appropriate for heavy metal ion indirect detection. Voltammetric techniques have been shown to be the most effective, sensitive, and time-efficient for heavy metal detection. In conclusion, because of the advantages of their huge surface area relative to their size and their electrocatalytic properties, the many nanoparticles that have been evaluated for the detection of heavy metal ions have shown substantial results.

Author Contributions

Conceptualization, S.G. and E.E.G.; methodology, S.G. and E.E.G.; software, E.C., V.L., E.E.G. and S.G.; verification, S.G. and E.E.G.; formal analysis, E.C., V.L., S.G. and E.E.G.; investigation, S.G. and E.E.G.; resources, S.G. and E.E.G.; data curation E.C., V.L., S.G. and E.E.G.; writing—original draft preparation, E.C., V.L., S.G. and E.E.G.; writing—review and editing, E.C., V.L., S.G. and E.E.G.; visualization, E.C., V.L., S.G. and E.E.G.; supervision, S.G. and E.E.G.; project administration, S.G. and E.E.G.;. funding acquisition, S.G. and E.E.G. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author.

Conflicts of Interest

The authors declare no conflict of interest.

References

Xhanari, K.; Finšgar, M. Recent advances in the modification of electrodes for trace metal analysis: A review. Analyst 2023, 148, 5808–5820. [Google Scholar] [CrossRef]
Keramari, V.; Karastogianni, S.; Girousi, S. New Prospects in the Electroanalysis of Heavy Metal Ions (Cd, Pb, Zn, Cu): Development and Application of Novel Electrode Surfaces. Methods Protoc. 2023, 6, 60. [Google Scholar] [CrossRef]
Jose, J.; Prakash, P.; Jeyaprabha, B.; Abraham, R.; Mathew, R.M.; Zacharia, E.S.; Thomas, V.; Thomas, J. Principle, design, strategies, and future perspectives of heavy metal ion detection using carbon nanomaterial-based electrochemical sensors: A review. J. Iran. Chem. Soc. 2023, 20, 775–791. [Google Scholar] [CrossRef]
Pratiwi, N.H.; Azis, M.Y.; Setiyanto, H. Review of Developments of Modified Carbon-Based Electrodes on Electrochemical Sensors for Water Environment Monitoring. Anal. Bioanal. Chem. Res. 2024, 11, 91–109. [Google Scholar] [CrossRef]
Diédhiou, I.; Fall, B.; Gaye, C.; Sall, M.L.; Diaw, A.K.D.; Gningue-Sall, D.; Fall, M.; Raouafi, N. Preparations and applications of organic conducting polymers/graphene composites in heavy metal ion sensing: A review. Int. J. Mater. Res. 2023, 114, 79–99. [Google Scholar] [CrossRef]
Tang, L.W.; Alias, Y.; Zakaria, R.; Woi, P.M. Progress in electrochemical sensing of heavy metals based on amino acids and its composites. Crit. Rev. Anal. Chem. 2023, 53, 869–886. [Google Scholar] [CrossRef]
Kaur, H.; Siwal, S.S.; Chauhan, G.; Saini, A.K.; Kumari, A.; Thakur, V.K. Recent advances in electrochemical-based sensors amplified with carbon-based nanomaterials (CNMs) for sensing pharmaceutical and food pollutants. Chemosphere 2022, 304, 135182. [Google Scholar] [CrossRef]
Zheng, J.; Rahim, M.A.; Tang, J.; Allioux, F.M. Post-transition metal electrodes for sensing heavy metal ions by stripping voltammetry. Adv. Mater. Technol. 2022, 7, 2100760. [Google Scholar] [CrossRef]
Kabata-Pendias, A. Trace Elements in Soils and Plants, 4th ed.; Taylor and Francis Group: Ann Arbor, MI, USA, 2010; ISBN 9781420093704. [Google Scholar]
Golia, E.E.; Diakoloukas, V. Soil parameters affecting the levels of potentially harmful metals in Thessaly area, Greece: A robust quadratic regression approach of soil pollution prediction. Environ. Sci. Pollut. Res. Int. 2022, 29, 29544–29561. [Google Scholar] [CrossRef]
Angelaki, A.; Dionysidis, A.; Sihag, P.; Golia, E.E. Assessment of Contamination Management Caused by Copper and Zinc Cations Leaching and Their Impact on the Hydraulic Properties of a Sandy and a Loamy Clay Soil. Land 2022, 11, 290. [Google Scholar] [CrossRef]
Papadimou, S.G.; Golia, E.E. Green and sustainable practices for an energy plant cultivation on naturally contaminated versus spiked soils. The impact of ageing soil pollution in the circular economy framework. Environ. Res. 2024, 246, 118130. [Google Scholar] [CrossRef] [PubMed]
Golia, E.; Dimirkou, A.; Floras, S.A. Spatial monitoring of arsenic and heavy metals in the Almyros area, Central Greecelectrode Statistical approach for assessing the sources of contamination. Environ. Monit. Assess. 2015, 187, 399. [Google Scholar] [CrossRef] [PubMed]
Liava, V.; Golia, E.E. Effect of microplastics used in agronomic practices on agricultural soil properties and plant functions: Potential contribution to the circular economy of rural areas. Waste Manag. Res. 2024. [Google Scholar] [CrossRef] [PubMed]
Papadimou, S.G.; Barbayiannis, N.; Golia, E.E. Preliminary investigation of the use of Silybum marianum (L.) Gaertn. as a Cd accumulator in contaminated Mediterranean soils: The relationships among cadmium (Cd) soil fractions and plant Cd content. Euro-Mediterr. J. Environ. Integr. 2024, 9, 405–417. [Google Scholar] [CrossRef]
Vasilou, C.; Tsiropoulos, N.G.; Golia, E.E. Phytoremediation & Valorization of Cu-contaminated Soils through Cannabis sativa (L.) Cultivation: A Smart Way to Produce Cannabidiol (CBD) in Mediterranean Soils. Waste Biomass Valor. 2024, 15, 1711–1724. [Google Scholar] [CrossRef]
Keramari, V.; Papadimou, S.G.; Golia, E.E.; Girousi, S. Bismuth Film along with dsDNA-Modified Electrode Surfaces as Promising (bio)Sensors in the Analysis of Heavy Metals in Soils. Biosensors 2024, 14, 310. [Google Scholar] [CrossRef] [PubMed]
Ali, H.; Khan, E. What are heavy metals? Long-standing controversy over the scientific use of the term ‘heavy metals’—Proposal of a comprehensive. Toxicol. Environ. Chem. 2018, 100, 6–19. [Google Scholar] [CrossRef]
Stankovic, S.; Kalaba, P.; Stankovic, A.R. Biota as toxic metal indicators. Environ. Chem. Lett. 2014, 12, 63–84. [Google Scholar] [CrossRef]
Kissinger, P.T.; Heineman, W.R. Laboratory Techniques in Electroanalytical Chemistry, 2nd ed.; CRC Press: Boca Raton, FL, USA, 1996. [Google Scholar]
Bard, A.J.; Faulkner, L.R.; White, H.S. Electrochemical Methods: Fundamentals and Applications, 3rd ed.; John Wiley & Sons: Hoboken, NJ, USA, 2022. [Google Scholar]
Oriakhi, C.O. Fundamentals of Electrochemistry. In Chemistry in Quantitative Language: Fundamentals of General Chemistry Calculations; Oxford Academic: New York, NY, USA, 2020; pp. 406–431. [Google Scholar] [CrossRef]
Hawkes, S.J. What is a “Heavy Metal”? J. Chem. Educ. 1997, 74, 1374. [Google Scholar] [CrossRef]
Duffus, J.H. Heavy Metals”—A Meaningless Term? Pure Appl. Chem. 2002, 74, 793–807. [Google Scholar] [CrossRef]
Wang, J. Analytical Electrochemistry, 2nd ed.; Wiley-VCH: Weinheim, Germany, 2000. [Google Scholar] [CrossRef]
Savéant, J.-M. Elements of Molecular and Biomolecular Electrochemistry: An Electrochemical Approach to Electron Transfer Chemistry; John Wiley & Sons: Hoboken, NJ, USA, 2006. [Google Scholar]
Kasuno, M.; Osuga, H.; Shina, K.; Yamazaki, T. Coulometric Anodic Stripping Voltammetry of Lead at Copper Column Electrode. Electroanalysis 2021, 33, 1502–1509. [Google Scholar] [CrossRef]
Huseinov, A.; Hoque, A.; Ruble, K.A.; Dee, B.J.; Alvarez, N.T. Reagentless Dissolution and Quantification of Particulate Lead in Tap Water via Membrane Electrolysis. Anal. Chem. 2023, 95, 9297–9303. [Google Scholar] [CrossRef] [PubMed]
Pengou, M.; Ngassa, G.B.; Boutianala, M.; Tchakouté, H.K.; Nanseu-Njiki, C.P.; Ngameni, E. Geopolymer cement–modified carbon paste electrode: Application to electroanalysis of traces of lead(II) ions in aqueous solution. J. Solid State Electrochem. 2021, 25, 1183–1195. [Google Scholar] [CrossRef]
Rahm, C.; Torres-Canas, F.; Gupta, P.; Poulin, P.; Alvarez, N.T. Inkjet Printed Multi-walled Carbon Nanotube Sensor for the Detection of Lead in Drinking Water. Electroanalysis 2020, 32, 1533–1545. [Google Scholar] [CrossRef]
Chen, X.; Lu, K.; Lin, D.; Li, Y.; Yin, S.; Zhang, Z.; Tang, M.; Chen, G. Hierarchical Porous Tubular Biochar Based Sensor for Detection of Trace Lead (II). Electroanalysis 2021, 33, 473–482. [Google Scholar] [CrossRef]
Zhong, J.; Zhao, H.; Cheng, Y.; Feng, T.; Lan, M.; Zuo, S. A high-performance electrochemical sensor for the determination of Pb(II) based on conductive dopamine polymer doped polypyrrole hydrogel. J. Electroanal. Chem. 2021, 902, 115815. [Google Scholar] [CrossRef]
Jalali Sarvestani, M.R.; Madrakian, T.; Afkhami, A. Ultra-trace levels voltammetric determination of Pb²⁺ in the presence of Bi³⁺ at food samples by a Fe₃O₄@Schiff base Network1 modified glassy carbon electrode. Talanta 2022, 250, 123716. [Google Scholar] [CrossRef] [PubMed]
Wang, C.-T.; Chen, W.-S.; Fan, K.-H.; Chiang, C.-Y.; Wu, C.-W. Bismuth and nitrogen co-doped graphene oxide for efficient electrochemical sensing of Pb(II) by synergistic dual-site interaction. J. Solid State Electrochem. 2022, 26, 2699–2711. [Google Scholar] [CrossRef]
Wang, C.; Niu, Q.; Liu, D.; Dong, X.; You, T. Electrochemical sensor based on Bi/Bi₂O₃ doped porous carbon composite derived from Bi-MOFs for Pb²⁺ sensitive detection. Talanta 2023, 258, 124281. [Google Scholar] [CrossRef]
Guo, X.; Zhang, Y.; Ge, H.; Zhang, J.; Yang, P.; Wu, Z. Facile fabrication of 2D MXene loading Co-doped Prussian blue nanoparticles for ultrasensitive electrochemical assay of trace lead ion. J. Electroanal. Chem. 2023, 935, 117320. [Google Scholar] [CrossRef]
Guo, C.; Wang, C.; Sun, H.; Dai, D.; Gao, H. A simple electrochemical sensor based on rGO/MoS₂/CS modified GCE for highly sensitive detection of Pb(ii) in tobacco leaves. RSC Adv. 2021, 11, 29590–29597. [Google Scholar] [CrossRef]
Liu, N.; Zhao, G.; Liu, G. Coupling Square Wave Anodic Stripping Voltammetry with Support Vector Regression to Detect the Concentration of Lead in Soil under the Interference of Copper Accurately. Sensors 2020, 20, 6792. [Google Scholar] [CrossRef]
Jaber, L.; Elgamouz, A.; Kawde, A.-N. An insight to the filtration mechanism of Pb(II) at the surface of a clay ceramic membrane through its preconcentration at the surface of a graphite/clay composite working electrode. Arab. J. Chem. 2022, 15, 104303. [Google Scholar] [CrossRef]
Barros, T.M.; de Araújo, D.M.; de Melo, A.T.L.; Martínez-Huitle, C.A.; Vocciante, M.; Ferro, S.; dos Santos, E.V. An Electroanalytical Solution for the Determination of Pb²⁺ in Progressive Hair Dyes Using the Cork–Graphite Sensor. Sensors 2022, 22, 1466. [Google Scholar] [CrossRef]
Liu, Y.; Chang, C.; Xue, Q.; Wang, R.; Chen, L.; Liu, Z.; He, L. Highly efficient detection of Pb(II) ion in water by polypyrrole and metal-organic frame modify glassy carbon electrode. Diam. Relat. Mater. 2022, 130, 109477. [Google Scholar] [CrossRef]
Xu, C.; Liu, J.; Bi, Y.; Ma, C.; Bai, J.; Hu, Z.; Zhou, M. Biomass derived worm-like nitrogen-doped-carbon framework for trace determination of toxic heavy metal lead (II). Anal. Chim. Acta 2020, 1116, 16–26. [Google Scholar] [CrossRef]
Zhou, Y.; Zhou, R.; Zhang, C.; Yi, Y.; He, Y.; Zhu, G. Recent Advances in Electrochemical Sensing of Lead Ion. J. Electrochem. Soc. 2024, 171, 016504. [Google Scholar] [CrossRef]
Wang, Y.-R.; Zhai, W.-Y.; Liu, Y.-Q. Study on Cd²⁺ Determination Using Bud-like Poly-L-Tyrosine/Bi Composite Film Modified Glassy Carbon Electrode Combined with Eliminating of Cu²⁺ Interference by Electrodeposition. Electroanalysis 2021, 33, 744–754. [Google Scholar] [CrossRef]
Feng, J.; Qi, J. Facile synthesis of graphene oxide coated 3D bimetallic oxide MnO₂/Bi₂O₃ microspheres for voltammetric detection of cadmium ion in water. J. Solid State Chem. 2023, 322, 124007. [Google Scholar] [CrossRef]
Garg, N.; Deep, A.; Sharma, A.L. Sensitive Detection of Cadmium Using Amine-Functionalized Fe-MOF by Anodic Stripping Voltammetry. Ind. Eng. Chem. Res. 2023, 62, 9735–9746. [Google Scholar] [CrossRef]
Jiang, L.; Ma, M.; Lin, C.; Yang, M.; Fang, L.; Liu, J.; Zhao, N.; Huang, X. Uniform manganese-loaded titanium dioxide nanotube arrays for accurate detection of trace Cd²⁺ in water, soil and tea: Enhanced stability and sensitivity. Chem. Eng. J. 2020, 400, 125972. [Google Scholar] [CrossRef]
Levanen, G.; Dali, A.; Leroux, Y.; Lupoi, T.; Betelu, S.; Michel, K.; Ababou-Girard, S.; Hapiot, P.; Dahech, I.; Cristea, C.; et al. Specific electrochemical sensor for cadmium detection: Comparison between monolayer and multilayer functionalization. Electrochim. Acta 2023, 464, 142962. [Google Scholar] [CrossRef]
Gao, J.; Qiu, C.; Qu, W.; Zhuang, Y.; Wang, P.; Yan, Y.; Wu, Y.; Zeng, Z.; Huang, G.; Deng, R.; et al. Detection of Cd²⁺ based on Nano-Fe₃O₄/MoS₂/Nafion/GCE sensor. Anal. Sci. 2023, 39, 1445–1454. [Google Scholar] [CrossRef] [PubMed]
Lu, H.; Ke, Z.; Feng, L.; Liu, B. Voltammetric sensing of Cd(II) at ZIF-8/GO modified electrode: Optimization and field measurements. Chemosphere 2023, 329, 138710. [Google Scholar] [CrossRef] [PubMed]
Maity, S.; Deshmukh, S.; Roy, S.S.; Dhar, B.B. Selenium-doped Graphite for Electrochemical Sensing and Adsorption of Hg(II) and Cd(II) Ions. ChemElectroChem 2023, 10, 202201044. [Google Scholar] [CrossRef]
Park, S.; Maier, C.S.; Koley, D. Anodic stripping voltammetry on a carbon-based ion-selective electrode. Electrochim. Acta 2021, 390, 138855. [Google Scholar] [CrossRef] [PubMed]
Zhu, G.; Su, J.; Zhang, B.; Liu, J. Electrospun amino-containing organosilica gel nanofibers for the ultrasensitive determination of Cu(II). J. Electroanal. Chem. 2021, 882, 114976. [Google Scholar] [CrossRef]
Alasağ, Ö.; Alpat, Ş.; Alpat, S.K. Voltammetric Determination of Copper by Biosorption-based Mesorhizobium Opportonistum Modified Microbial Biosensor. Electroanalysis 2022, 34, 1701–1710. [Google Scholar] [CrossRef]
Li, G.; Feng, S.; Yan, L.; Yang, L.; Huo, B.; Wang, L.; Luo, S.; Yang, D. Direct electrochemical detection of Cu(Ⅱ) ions in juice and tea beverage samples using MWCNTs-BMIMPF6-Nafion modified GCE electrodes. Food Chem. 2023, 404, 134609. [Google Scholar] [CrossRef]
Challier, L.; Forget, A.; Bazin, C.; Tanniou, S.; Le Doare, J.; Davy, R.; Bernard, H.; Tripier, R.; Laes-Huon, A.; Le Poul, N.L. An ultrasensitive and highly selective nanomolar electrochemical sensor based on an electrocatalytic peak shift analysis approach for copper trace detection in water. Electrochim. Acta 2022, 434, 141298. [Google Scholar] [CrossRef]
Fayazi, M.; Ghanei-Motlagh, M.; Karami, C. Application of magnetic nanoparticles modified with L-cysteine for pre-concentration and voltammetric detection of copper(II). Microchem. J. 2022, 181, 107652. [Google Scholar] [CrossRef]
Magarelli, G.; da Silva, J.G.; Ribeiro, C.L.; de Freita, T.V.; Rodrigues, M.A.; de Souza Gil, E.; Maraccinni, P.; de Souza, J.R.; de Castro, C.S.P.; Bemquerer, M.P. A voltammetric peptide biosensor for Cu²⁺ metal ion quantification in coffee seeds. J. Inorg. Biochem. 2024, 251, 112441. [Google Scholar] [CrossRef] [PubMed]
Ribeiro, M.M.A.C.; Rocha, R.G.; Munoz, R.A.A.; Richter, E.M. A Batch Injection Analysis System with Square-wave Voltammetric Detection for Fast and Simultaneous Determination of Zinc and Ascorbic Acid. Electroanalysis 2021, 33, 90–96. [Google Scholar] [CrossRef]
Caetano, M.; dos Santos, M.M.C.; Rosa, N.; Carvalho, I.; Rodríguez, J.G.; Belzunce-Segarra, M.J.; Menchaca, I.; Larreta, J.; Sanz, M.R.; Millán-Gabet, V.; et al. Metals concentrations in transitional and coastal waters by ICPMS and voltammetry analysis of spot samples and passive samplers (DGT). Mar. Pollut. Bull. 2022, 179, 113715. [Google Scholar] [CrossRef] [PubMed]
Drwal, K.; Górska, Z.; Bończak, P.; Krasnodębska-Ostręga, B. Voltammetric Analysis of Cadmium and Lead (Undesirable Elements) in Brine, Supported by Solid Phase Extraction—The Right Solution of the Analytical Challenge. Electroanalysis 2023, 35, e202200397. [Google Scholar] [CrossRef]
Obrez, D.; Kolar, M.; Tasić, N.; Hočevar, S.B. Study of different types of copper electrodes for anodic stripping voltammetric detection of trace metal ions. Electrochim. Acta 2023, 457, 142480. [Google Scholar] [CrossRef]
de Oliveira, C.; Maciel, J.V.; Christ-Ribeiro, A.; Guarda, A.; Dias, D. A Voltammetric Approach for the Simultaneous Determination of Cd and Pb in Water Applying Carbon Paste Electrode Modified with Bismuth Film. J. Anal. Chem. 2022, 77, 369–375. [Google Scholar] [CrossRef]
Colozza, N.; Cacciotti, I.; Moscone, D.; Arduini, F. Effects of Humidity, Temperature and Bismuth Electrodeposition on Electroanalytical Performances of Nafion-coated Printed Electrodes for Cd²⁺ and Pb²⁺ Detection. Electroanalysis 2020, 32, 345–357. [Google Scholar] [CrossRef]
Majidian, M.; Raoof, J.B.; Hosseini, S.R.; Ojani, R.; Barek, J.; Fischer, J. Novel Type of Carbon Nanotube Paste Electrode Modified by Sb₂O₃ for Square Wave Anodic Stripping Voltammetric Determination of Cd²⁺ and Pb²⁺. Electroanalysis 2020, 32, 2260–2265. [Google Scholar] [CrossRef]
Mazzaracchio, V.; Tshwenya, L.; Moscone, D.; Arduini, F.; Arotiba, O.A. A Poly(Propylene Imine) Dendrimer and Carbon Black Modified Flexible Screen Printed Electrochemical Sensor for Lead and Cadmium Co-detection. Electroanalysis 2020, 32, 3009–3016. [Google Scholar] [CrossRef]
Zhao, G.; Sedki, M.; Ma, S.; Villarreal, C.; Mulchandani, A.; Jassby, D. Bismuth subcarbonate decorated reduced graphene oxide nanocomposite for the sensitive stripping voltammetry analysis of Pb(II) and Cd(II) in water. Sensors 2020, 20, 6085. [Google Scholar] [CrossRef]
Seifi, A.; Afkhami, A.; Madrakian, T. Highly sensitive and simultaneous electrochemical determination of lead and cadmium ions by poly(thionine)/MWCNTs-modified glassy carbon electrode in the presence of bismuth ions. J. Appl. Electrochem. 2022, 52, 1513–1523. [Google Scholar] [CrossRef]
Zhang, X.; An, D.; Bi, Z.; Shan, W.; Zhu, B.; Zhou, L.; Yu, L.; Zhang, H.; Xia, S.; Qiu, M. Ti₃C₂-MXene@N-doped carbon heterostructure-based electrochemical sensor for simultaneous detection of heavy metals. J. Electroanal. Chem. 2022, 911, 116239. [Google Scholar] [CrossRef]
Shishov, A.; Volodina, N.; Semenova, E.; Navolotskaya, D.; Ermakov, S.; Bulatov, A. Reversed-phase dispersive liquid-liquid microextraction based on decomposition of deep eutectic solvent for the determination of lead and cadmium in vegetable oil. Food Chem. 2022, 373, 131456. [Google Scholar] [CrossRef] [PubMed]
Wang, Y.; Wu, X.; Sun, J.; Wang, C.; Zhu, G.; Bai, L.-P.; Jiang, Z.-H.; Zhang, W. Stripping voltammetric determination of cadmium and lead ions based on a bismuth oxide surface-decorated nanoporous bismuth electrode. Electrochem. Commun. 2022, 136, 107233. [Google Scholar] [CrossRef]
Gayathri, J.; Sivalingam, S.; Narayanan, S.S. Novel synthesized SABA/MWCNTs composite to detect Cd²⁺ and Pb²⁺ ions in real samples of rice water, tobacco extract and raw milk. J. Mol. Liq. 2023, 387, 122586. [Google Scholar] [CrossRef]
Ong, C.S.; Zaharum, N.H.B.; Nor, N.M.; Ahmad, A.L.; Ng, Q.H.; Razak, K.A.; Low, S.C. Morphology and atomic configuration control of heavy metal attraction modified layer on screen-printed electrode to enhance electrochemical sensing performance. J. Electroanal. Chem. 2023, 939, 117477. [Google Scholar] [CrossRef]
Tapia, M.A.; Pérez-Ràfols, C.; Gusmão, R.; Serrano, N.; Sofer, Z.; Díaz-Cruz, J.M. Enhanced voltammetric determination of metal ions by using a bismuthene-modified screen-printed electrode. Electrochim. Acta 2020, 362, 137144. [Google Scholar] [CrossRef]
Lalmalsawmi, J.; Sarikokba; Tiwari, D.; Kim, D.-J. Simultaneous detection of Cd²⁺ and Pb²⁺ by differential pulse anodic stripping voltammetry: Use of highly efficient novel Ag0(NPs) decorated silane grafted bentonite material. J. Electroanal. Chem. 2022, 918, 116490. [Google Scholar] [CrossRef]
Zhou, L.; Sekar, S.; Chen, J.; Lee, S.; Kim, D.Y.; Manikandan, R. A polyrutin/AgNPs coated GCE for simultaneous anodic stripping voltammetric determination of Pb(II) and Cd(II)ions in environmental samples. Colloids Surf. A Physicochem. Eng. 2022, 648, 129082. [Google Scholar] [CrossRef]
Muna, G.W.; Barrera, E.; Robinson, L.; Majeed, H.; Jones, K.; Damschroder, A.; Vila, A. Electroanalytical performance of a Bismuth/Antimony composite glassy carbon electrode in detecting lead and cadmium. Electroanalysis 2023, 35, 202300019. [Google Scholar] [CrossRef]
Kim, M.; Park, J.; Park, H.; Jo, W.; Lee, W.; Park, J. Detection of Heavy Metals in Water Environment Using Nafion-Blanketed Bismuth Nanoplates. ACS Sustain. Chem. Eng. 2023, 11, 6844–6855. [Google Scholar] [CrossRef]
Tapia, M.A.; Pérez-Ràfols, C.; Oliveira, F.M.; Gusmão, R.; Serrano, N.; Sofer, Z.; Díaz-Cruz, J.M. Antimonene-Modified Screen-Printed Carbon Nanofibers Electrode for Enhanced Electroanalytical Response of Metal Ions. Chemosensors 2023, 11, 219. [Google Scholar] [CrossRef]
Huo, R.; Liu, L.; Chanthasa, C.; Okazaki, T.; Sazawa, K.; Sugawara, K.; Kuramitz, H. Microdroplet anodic stripping voltammetry at the in situ preparing antimony-modified rotating disk electrode for determination of Cd(II) and Pb(II). Electroanalysis 2023, 35, 202200528. [Google Scholar] [CrossRef]
Karazan, Z.M.; Roushani, M. Selective determination of cadmium and lead ions in different food samples by poly (riboflavin)/carbon black-modified glassy carbon electrode. Food Chem. 2023, 423, 136283. [Google Scholar] [CrossRef]
Mendonça, M.Z.M.; de Oliveira, F.M.; Petroni, J.M.; Lucca, B.G.; da Silva, R.A.B.; Cardoso, V.L.; de Melo, E.I. Biochar from coffee husks: A green electrode modifier for sensitive determination of heavy metal ions. J. Appl. Electrochem. 2023, 53, 1461–1471. [Google Scholar] [CrossRef]
Liu, N.; Ye, W.; Liu, G.; Zhao, G. Improving the accuracy of stripping voltammetry detection of Cd²⁺ and Pb²⁺ in the presence of Cu²⁺ and Zn²⁺ by machine learning: Understanding and inhibiting the interactive interference among multiple heavy metals. Anal. Chim. Acta 2022, 1213, 339956. [Google Scholar] [CrossRef]
Baghayeri, M.; Alinezhad, H.; Fayazi, M.; Tarahomi, M.; Ghanei-Motlagh, R.; Maleki, B. A novel electrochemical sensor based on a glassy carbon electrode modified with dendrimer functionalized magnetic graphene oxide for simultaneous determination of trace Pb(II) and Cd(II). Electrochim. Acta 2019, 312, 80–88. [Google Scholar] [CrossRef]
Zhao, G.; Liu, G. A Portable Electrochemical System for the On-Site Detection of Heavy Metals in Farmland Soil Based on Electrochemical Sensors. IEEE Sens. J. 2018, 18, 5645–5655. [Google Scholar] [CrossRef]
Liu, N.; Zhao, G.; Ye, W.; Wang, J.; Liu, G. VUV-H₂O₂ photolysis as a pretreatment method for improving the SWASV detection accuracies of Cd²⁺ and Pb²⁺ in soil extracts. J. Environ. Chem. Eng. 2022, 10, 107813. [Google Scholar] [CrossRef]
Liu, N.; Ye, W.; Zhao, G.; Liu, G. Release of free-state ions from fulvic acid-heavy metal complexes via VUV/H₂O₂ photolysis: Photodegradation of fulvic acids and recovery of Cd²⁺ and Pb²⁺ stripping voltammetry currents. Environ. Pollut. 2022, 315, 120420. [Google Scholar] [CrossRef]
Ye, W.; Liu, N.; Zhao, G.; Liu, G. Accurate Detection of Cd²⁺ and Pb²⁺ Concentrations in Soils by Stripping Voltammetry Peak Areas under the Mutual Interference of Multiple Heavy Metals. Metals 2023, 13, 270. [Google Scholar] [CrossRef]
Antunović, V.; Tripković, T.; TomaŠević, B.; BaoŠić, R.; Jelić, D.; Lolić, A. Voltammetric Determination of Lead and Copper in Wine by Modified Glassy Carbon Electrode. Anal. Sci. 2021, 37, 353–358. [Google Scholar] [CrossRef]
Magni, M.; Sironi, D.; Ferri, M.; Trasatti, S.; Campisi, S.; Gervasini, A.; Papacchini, M.; Cristiani, P. High-Content Hydroxyapatite Carbon Composites for the Electrochemical Detection of Heavy Metal Cations in Water. ChemElectroChem 2023, 10, 202201017. [Google Scholar] [CrossRef]
Zhang, Y.; Yu, H.; Liu, T.; Li, W.; Hao, X.; Lu, Q.; Liang, X.; Liu, F.; Liu, F.; Wang, C.; et al. Highly sensitive detection of Pb²⁺ and Cu²⁺ based on ZIF-67/MWCNT/Nafion-modified glassy carbon electrode. Anal. Chim. Acta 2020, 1124, 166–175. [Google Scholar] [CrossRef] [PubMed]
Soares, P.I.; Lima, T.M.; do Nascimento, L.A.; Coelho, R.M.; Franco, D.L.; Pereira, A.C.; Ferreira, L.F. Co-detection of Copper and Lead in Artisanal Sugarcane Spirit Using Caffeic Acid-modified Graphite Electrodes. Electroanalysis 2023, 35, 202200302. [Google Scholar] [CrossRef]
Buljac, M.; Radić, J.; Buzuk, M.; Škugor Rončević, I.; Vladislavić, N.; Krivić, D.; Marijanović, A. Application of the Stripping Voltammetry Method for the Determination of Copper and Lead Hyperaccumulation Potential in Lunaria annua L. Chemosensors 2022, 10, 52. [Google Scholar] [CrossRef]
Maciel, C.C.; de Barros, A.; Mazali, I.O.; Ferreira, M. Flexible biodegradable electrochemical sensor of PBAT and CNDs composite for the detection of emerging pollutants. J. Electroanal. Chem. 2023, 940, 117491. [Google Scholar] [CrossRef]
Al-Hossainy, A.F. Simultaneous determination of Cd(II) and Cu(II) using stripping voltammetry in groundwater, soil and Alhagi maurorum plants in industrial and urban areas in Northern Border, Saudi Arabia with luminol as a chelating agent. Water Sci. Technol. 2015, 72, 1127–1139. [Google Scholar] [CrossRef] [PubMed]
Sullivan, C.; Lu, D.; Brack, E.; Drew, C.; Kurup, P. Voltammetric codetection of arsenic(III) and copper(II) in alkaline buffering system with gold nanostar modified electrodes. Anal. Chim. Acta 2020, 1107, 63–73. [Google Scholar] [CrossRef]
Nodehi, M.; Baghayeri, M.; Veisi, H. Preparation of GO/Fe₃O₄@PMDA/AuNPs nanocomposite for simultaneous determination of As³⁺ and Cu²⁺ by stripping voltammetry. Talanta 2021, 230, 122288. [Google Scholar] [CrossRef] [PubMed]
Melucci, D.; Locatelli, M.; Locatellii, C. Trace level voltammetric determination of heavy metals and total mercury in tea matrices (Camellia sinensis). Food Chem. Toxicol. 2013, 62, 901–907. [Google Scholar] [CrossRef] [PubMed]
Poudel, A.; Shyam Sunder, G.S.; Rohanifar, A.; Adhikari, S. Electrochemical determination of Pb²⁺ and Cd²⁺ with a poly(pyrrole-1-carboxylic acid) modified electrode. J. Electroanal. Chem. 2022, 911, 116221. [Google Scholar] [CrossRef]
Kiliç, H.D.; Deveci, S.; Dönmez, K.B.; Çetinkaya, E.; Karadağ, S.; Doğu, M. Application of stripping voltammetry method for the analysis of available copper, zinc and manganese contents in soil samples. Int. J. Environ. Analyt. Chem. 2018, 98, 308–322. [Google Scholar] [CrossRef]
Walters, J.G.; Ahmed, S.; Rodríguez, I.M.T.; O’Neil, G.D. Trace Analysis of Heavy Metals (Cd, Pb, Hg) Using Native and Modified 3D Printed Graphene/Poly(Lactic Acid) Composite Electrodes. Electroanalysis 2020, 32, 859–866. [Google Scholar] [CrossRef]
Zhang, W.; Liu, C.; Liu, F.; Zou, X.; Xu, Y.; Xu, X. A smart-phone-based electrochemical platform with programmable solid-state-microwave flow digestion for determination of heavy metals in liquid food. Food Chem. 2020, 303, 125378. [Google Scholar] [CrossRef] [PubMed]
Djemmoe, L.G.; Njanja, E.; Tchieno, F.M.M.; Ndinteh, D.T.; Ndungu, P.G.; Tonle, I.K. Activated Hordeum vulgare L. dust as carbon paste electrode modifier for the sensitive electrochemical detection of Cd²⁺, Pb²⁺ and Hg²⁺ ions. Int. J. Environ. Anal. Chem. 2020, 100, 1429–1445. [Google Scholar] [CrossRef]
Hermouche, L.; Aqil, Y.; Abbi, K.; El Hamdouni, Y.; Ouanji, F.; El Hajjaji, S.; El Mahi, M.; Lotfi, E.M.; Labjar, N. Eco-friendly modified carbon paste electrode by Bigarreau Burlat kernel shells for simultaneous trace detection of cadmium, lead, and copper. Chem. Data Collect. 2021, 32, 100642. [Google Scholar] [CrossRef]
Gupta, P.; Rahm, C.; Jiang, D.; Gupta, V.K.; Heineman, W.R.; Justin, G.; Alvarez, N.T. Parts per trillion detection of heavy metals in as-is tap water using carbon nanotube microelectrodes. Anal. Chim. Acta 2021, 1155, 338353. [Google Scholar] [CrossRef]
Abdou, M.; Tercier-Waeber, M.-L. New insights into trace metal speciation and interaction with phytoplankton in estuarine coastal waters. Mar. Pollut. Bull. 2022, 181, 113845. [Google Scholar] [CrossRef]
Manjunatha Kumara, K.S.; Nagaraju, D.H.; Yhobu, Z.; Nayan Kumar, H.N.; Budagumpi, S.; Kumar Bose, S.; Shivakumar, P.; Palakollu, V.N. Tuning the Surface Functionality of Fe₃O₄ for Sensitive and Selective Detection of Heavy Metal Ions. Sensors 2022, 22, 8895. [Google Scholar] [CrossRef] [PubMed]
Belcovici, A.; Fort, C.I.; Mureşan, L.E.; Perhaiţa, I.; Borodi, G.; Turdean, G.L. Zinc oxide nanostructured platform for electrochemical detection of heavy metals. Electroanalysis 2023, 35, 202200395. [Google Scholar] [CrossRef]
Kulpa-Koterwa, A.; Ryl, J.; Górnicka, K.; Niedziałkowski, P. New nanoadsorbent based on magnetic iron oxide containing 1,4,7,10-tetraazacyclododecane in outer chain (Fe₃O₄@SiO₂-cyclen) for adsorption and removal of selected heavy metal ions Cd²⁺, Pb²⁺, Cu²⁺. J. Mol. Liq. 2022, 368, 120710. [Google Scholar] [CrossRef]
Shen, Y.; Xue, Y.; Xia, X.; Zeng, S.; Zhang, J.; Li, K. Metallic-like boron-modified bio-carbon electrodes for simultaneous electroanalysis for Cd²⁺, Pb²⁺ and Cu²⁺: Theoretical insight into the role of CxBOy(H). Carbon 2023, 214, 118350. [Google Scholar] [CrossRef]
Partheni, V.; Svarnias, K.; Economou, A.; Kokkinos, C.; Fielden, P.R.; Baldock, S.J.; Goddard, N.J. Voltammetric Determination of Trace Heavy Metals by Sequential-injection Analysis at Plastic Fluidic Chips with Integrated Carbon Fiber-based Electrodes. Electroanalysis 2021, 33, 1930–1935. [Google Scholar] [CrossRef]
Ustabasi, G.S.; Yilmaz, I.; Ozcan, M.; Cetinkaya, E. Simultaneous, Selective and Highly Sensitive Voltammetric Determination of Lead, Cadmium, and Zinc via Modified Pencil Graphite Electrodes. Electroanalysis 2022, 34, 1237–1244. [Google Scholar] [CrossRef]
Ngoensawat, U.; Pisuchpen, T.; Sritana-Anant, Y.; Rodthongkum, N.; Hoven, V.P. Conductive electrospun composite fibers based on solid-state polymerized Poly(3,4-ethylenedioxythiophene) for simultaneous electrochemical detection of metal ions. Talanta 2022, 241, 123253. [Google Scholar] [CrossRef] [PubMed]
Mahmoudi-Moghaddam, H.; Amiri, M.; Javar, H.A.; Yousif, Q.A.; Salavati-Niasari, M. Green synthesis and characterization of Tb-Fe-O-Cu ceramic nanocomposite and its application in simultaneous electrochemical sensing of zinc, cadmium and lead. Arab. J. Chem. 2022, 15, 103988. [Google Scholar] [CrossRef]
Shalaby, E.A.; Beltagi, A.M.; Hathoot, A.A.; Azzem, M.A. Simultaneous voltammetric sensing of Zn²⁺, Cd²⁺, and Pb²⁺ using an electrodeposited Bi-Sb nanocomposite modified carbon paste electrode. RSC Adv. 2023, 13, 7118–7128. [Google Scholar] [CrossRef]
Shao, Y.; Dong, Y.; Bin, L.; Fan, L.; Wang, L.; Yuan, X.; Li, D.; Liu, X.; Zhao, S. Application of gold nanoparticles/polyaniline-multi-walled carbon nanotubes modified screen-printed carbon electrode for electrochemical sensing of zinc, lead, and copper. Microchem. J. 2021, 170, 106726. [Google Scholar] [CrossRef]
Biasi, A.D.L.M.; Takara, E.A.; Scala-Benuzzi, M.L.; Valverde, A.M.; Gómez, N.N.; Messina, G.A. Modification of electrodes with polymer nanocomposites: Application to the simultaneous determination of Zn(II), Cd(II), and Cu(II) in water samples. Anal. Chim. Acta 2023, 1273, 341499. [Google Scholar] [CrossRef] [PubMed]
Afkhami, A.; Moosavi, R.; Madrakian, T.; Keypour, H.; Ramezani-Aktij, A.; Mirzaei-Monsef, M. Construction and Application of an Electrochemical Sensor for Simultaneous Determination of Cd(II), Cu(II) and 864 Hg(II) in Water and Foodstuff Samples. Electroanalysis 2014, 26, 786–795. [Google Scholar] [CrossRef]
Afkhami, A.; Soltani-Felehgari, F.; Madrakian, T.; Ghaedi, H.; Rezaeivala, M. Fabrication and application of a new modified electrochemical sensor using nano-silica and a newly synthesized Schiff base for simultaneous determination of Cd²⁺, Cu²⁺ and Hg²⁺ ions in water and some foodstuff samples. Anal. Chim. Acta 2013, 771, 21–30. [Google Scholar] [CrossRef]
Naseri, M.; Mohammadniaei, M.; Ghosh, K.; Sarkar, S.; Sankar, R.; Mukherjee, S.; Pal, S.; Dezfouli, E.A.; Halder, A.; Qiao, J.; et al. A Robust Electrochemical Sensor Based on Butterfly-shaped Silver Nanostructure for Concurrent Quantification of Heavy Metals in Water Samples. Electroanalysis 2023, 35, 202200114. [Google Scholar] [CrossRef]
Zhang, M.; Guo, W. Simultaneous electrochemical detection of multiple heavy metal ions in milk based on silica-modified magnetic nanoparticles. Food Chem. 2023, 406, 135034. [Google Scholar] [CrossRef] [PubMed]
Han, X.; Meng, Z.; Zhang, H.; Zheng, J. Fullerene-based anodic stripping voltammetry for simultaneous determination of Hg(II), Cu(II), Pb(II) and Cd(II) in foodstuff. Mikrochim. Acta 2018, 185, 274. [Google Scholar] [CrossRef]
Yıldız, C.; Bayraktepe, D.E.; Yazan, Z. Highly sensitive direct simultaneous determination of zinc(II), cadmium(II), lead(II), and copper(II) based on in-situ-bismuth and mercury thin-film plated screen-printed carbon electrode. Monatsh. Chem. 2021, 152, 1527–1537. [Google Scholar] [CrossRef]
Yıldız, C.; Bayraktepe, D.E.; Yazan, Z.; Önal, M. Bismuth nanoparticles decorated on Na-montmorillonite-multiwalled carbon nanotube for simultaneous determination of heavy metal ions- electrochemical methods. J. Electroanal. Chem. 2022, 910, 116205. [Google Scholar] [CrossRef]
Sarvestani, M.R.J.; Madrakian, T.; Afkhami, A. Simultaneous determination of Pb²⁺ and Hg²⁺ at food specimens by a Melamine-based covalent organic framework modified glassy carbon electrode. Food Chem. 2023, 402, 134246. [Google Scholar] [CrossRef]
Gayathri, J.; Sivalingam, S.; Narayanan, S.S. Synthesis and characterization of Schiff base ligand-mutliwalled carbon nanotubes as mercury-free electrochemical sensor for detecting toxic metals in aquatic treatment. Diam. Relat. Mater. 2023, 136, 109984. [Google Scholar] [CrossRef]
Nodehi, M.; Baghayeri, M.; Kaffash, A. Application of BiNPs/MWCNTs-PDA/GC sensor to measurement of Tl (1) and Pb (II) using stripping voltammetry. Chemosphere 2022, 301, 134701. [Google Scholar] [CrossRef] [PubMed]
Laghlimi, C.; Ziat, Y.; Moutcine, A.; Hammi, M.; Zarhri, Z.; Ifguis, O.; Chtaini, A. A new sensor based on graphite carbon paste modified by an organic molecule for efficient determination of heavy metals in drinking water. Chem. Data Collect. 2021, 31, 100595. [Google Scholar] [CrossRef]
Castro, S.V.F.; Lima, A.P.; Rocha, R.G.; Cardoso, R.M.; Montes, R.H.O.; Santana, M.H.P.; Richter, E.M.; Munoz, R.A.A. Simultaneous determination of lead and antimony in gunshot residue using a 3D-printed platform working as sampler and sensor. Anal. Chim. Acta 2020, 1130, 126–136. [Google Scholar] [CrossRef] [PubMed]
Banna, G.M.; Siegenthaler, J.; Benedict, A.; Allen, B.; Martinez, R.M.; Zhang, W.; Li, W. Heavy Metal Sensing in plant and soil solutions using carbon fiber electrode. Sens. Actuators A. Phys. 2024, 370, 115232. [Google Scholar] [CrossRef]

Figure 1. Negative effects of heavy metals in human health (Source: figure created by authors).

Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

Share and Cite

MDPI and ACS Style

Chatziathanasiou, E.; Liava, V.; Golia, E.E.; Girousi, S. Analytical Applications of Voltammetry in the Determination of Heavy Metals in Soils, Plant Tissues, and Water—Prospects and Limitations in the Co-Identification of Metal Cations in Environmental Samples. Analytica 2024, 5, 358-383. https://doi.org/10.3390/analytica5030023

AMA Style

Chatziathanasiou E, Liava V, Golia EE, Girousi S. Analytical Applications of Voltammetry in the Determination of Heavy Metals in Soils, Plant Tissues, and Water—Prospects and Limitations in the Co-Identification of Metal Cations in Environmental Samples. Analytica. 2024; 5(3):358-383. https://doi.org/10.3390/analytica5030023

Chicago/Turabian Style

Chatziathanasiou, Efthymia, Vasiliki Liava, Evangelia E. Golia, and Stella Girousi. 2024. "Analytical Applications of Voltammetry in the Determination of Heavy Metals in Soils, Plant Tissues, and Water—Prospects and Limitations in the Co-Identification of Metal Cations in Environmental Samples" Analytica 5, no. 3: 358-383. https://doi.org/10.3390/analytica5030023

Article Menu

Analytical Applications of Voltammetry in the Determination of Heavy Metals in Soils, Plant Tissues, and Water—Prospects and Limitations in the Co-Identification of Metal Cations in Environmental Samples

Abstract

1. Introduction

1.1. Heavy Metals

1.1.1. Determination of Metal Ions in Soil Samples

1.1.2. Identification of Metal Ions in Plants

1.2. Classical Methods the for Determination of Metal Ions in Soil Samples and Plants

Voltammetry—A Promising Analytical Method for Determination of Metal Ions

1.3. Applications of Voltammetry in the Analysis of a Single Heavy Metal

1.4. Determination of Pb

1.5. Determination of Cd

1.6. Determination of Cu

1.7. Determination of Zn

2. Applications of Voltammetric Analysis for Two Heavy Metals Simultaneously

2.1. Simultaneous Determination of Pb and Cd

2.2. Simultaneous Determination of Pb and Cu

2.3. Simultaneous Determination of Cd and Cu

2.4. Simultaneous Determination of Cu and As

2.5. Simultaneous Determination of Cu and Hg

3. Applications of Voltammetric Analysis for Three or More Heavy Metals Simultaneously

3.1. Simultaneous Determination of Cu, Mn, and Zn

3.2. Simultaneous Determination of Pb, Cd, and Hg

3.3. Simultaneous Determination of Pb, Cd, and Cu

3.4. Simultaneous Determination of Pb, Cd, and Zn

3.5. Simultaneous Determination of Pb, Cu, and Zn

3.6. Simultaneous Determination of Cd, Cu, and Zn

3.7. Simultaneous Determination of Cd, Cu, and Hg

3.8. Simultaneous Determination of Pb, Cd, Cu, and Hg

3.9. Simultaneous Determination of Pb, Cd, Cu, and Zn

3.10. Simultaneous Determination of Pb and Other Heavy Metals

4. Conclusions

Author Contributions

Funding

Data Availability Statement

Conflicts of Interest

References

Share and Cite

Article Metrics

Article Access Statistics

Further Information

Guidelines

MDPI Initiatives

Follow MDPI