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Chemosensors, Volume 12, Issue 10 (October 2024) – 22 articles

Cover Story (view full-size image): We present a methodology for the quantitative chemical sensing of target materials in an inspected solution by employing bioluminescent bioreporters as the sensing apparatus. Variations in the signal between different bacteria batches and changing environmental conditions are overcome via an in situ comparison between the responses produced by the inspected solution and a standard solution containing a known concentration of the target material. An extension of the measurable concentration range is obtained by parallel measurements of the responses produced by several types of bacteria, each sensitive to a different segment of the concentration range. This methodology was implemented in a module in which the bioluminescence signals produced by bioreporters that are exposed to the inspected and standard solutions are monitored in parallel. View this paper

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19 pages, 9872 KiB  
Article
A Portable Electronic Nose Coupled with Deep Learning for Enhanced Detection and Differentiation of Local Thai Craft Spirits
by Supakorn Harnsoongnoen, Nantawat Babpan, Saksun Srisai, Pongsathorn Kongkeaw and Natthaphon Srisongkram
Chemosensors 2024, 12(10), 221; https://doi.org/10.3390/chemosensors12100221 - 19 Oct 2024
Viewed by 1007
Abstract
In this study, our primary focus is the biomimetic design and rigorous evaluation of an economically viable and portable ‘e-nose’ system, tailored for the precise detection of a broad range of volatile organic compounds (VOCs) in local Thai craft spirits. This e-nose system [...] Read more.
In this study, our primary focus is the biomimetic design and rigorous evaluation of an economically viable and portable ‘e-nose’ system, tailored for the precise detection of a broad range of volatile organic compounds (VOCs) in local Thai craft spirits. This e-nose system is innovatively equipped with cost-efficient metal oxide gas sensors and a temperature/humidity sensor, ensuring comprehensive and accurate sensing. A custom-designed real-time data acquisition system is integrated, featuring gas flow control, humidity filters, dual sensing/reference chambers, an analog-to-digital converter, and seamless data integration with a laptop. Deep learning, utilizing a multilayer perceptron (MLP), is employed to achieve highly effective classification of local Thai craft spirits, demonstrated by a perfect classification accuracy of 100% in experimental studies. This work underscores the significant potential of biomimetic principles in advancing cost-effective, portable, and analytically precise e-nose systems, offering valuable insights into future applications of advanced gas sensor technology in food, biomedical, and environmental monitoring and safety. Full article
(This article belongs to the Special Issue Gas Sensors and Electronic Noses for the Real Condition Sensing)
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12 pages, 3336 KiB  
Article
Fast Determination and Source Apportionment of Eight Polycyclic Aromatic Hydrocarbons in PM10 Using the Chemometric-Assisted HPLC-DAD Method
by Ting Hu, Yitao Xia, You Wang, Li Lin, Rong An, Ling Xu and Xiangdong Qing
Chemosensors 2024, 12(10), 220; https://doi.org/10.3390/chemosensors12100220 - 18 Oct 2024
Viewed by 703
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds that are both toxic and hazardous to human health and ecological systems. In recent work, a novel analytical strategy based on the chemometric-assisted HPLC-DAD method was proposed for the quantification and source apportionment [...] Read more.
Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds that are both toxic and hazardous to human health and ecological systems. In recent work, a novel analytical strategy based on the chemometric-assisted HPLC-DAD method was proposed for the quantification and source apportionment of eight PAHs in PM10 samples. Compared to traditional chromatographic methods, this approach does not require the purification of complex PM10 samples. Instead, it utilizes a mathematical separation method to extract analytes’ profiles from overlapping chromatographic peaks, enabling precise quantification of PAHs in PM10. Firstly, 40 PM10 samples collected in Loudi city during two sampling periods were used for analysis. Subsequently, the second-order calibration method based on alternating trilinear decomposition (ATLD) was employed to handle the three-way HPLC-DAD data. Finally, the pollution sources of PAHs were analyzed by the feature component analysis method according to the obtained relative concentration matrix. For the validation model, the average recoveries of eight PAHs were between (88.8 ± 7.6)% and (105.6 ± 7.5)%, and the root-mean-square errors of prediction ranged from 0.03 μg mL−1 to 0.47 μg mL−1. The obtained limits of quantification for eight PAHs were in the range of 0.0050 μg mL−1 to 0.079 μg mL−1. For actual PM10 samples, results of the feature component analysis indicated that the main source of PAHs in PM10 may be traffic emissions and coal combustion. In summary, the proposed method provided a new and rapid analysis method for the accurate determination and source apportionment of PAHs in atmospheric aerosols. Full article
(This article belongs to the Special Issue Green Analytical Methods for Environmental and Food Analysis)
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15 pages, 9983 KiB  
Article
Adsorption and Sensing Properties of Ni-Modified InSe Monolayer Towards Toxic Gases: A DFT Study
by Jianhong Dong, Xiaoqian Qiu, Shuying Huang, Shaomin Lin, Lisha Liu and Huihui Xiong
Chemosensors 2024, 12(10), 219; https://doi.org/10.3390/chemosensors12100219 - 18 Oct 2024
Viewed by 910
Abstract
The emission of toxic gases from industrial production has intensified issues related to atmospheric pollution and human health. Consequently, the effective real-time monitoring and removal of these harmful gases have emerged as significant challenges. In this work, the density functional theory (DFT) method [...] Read more.
The emission of toxic gases from industrial production has intensified issues related to atmospheric pollution and human health. Consequently, the effective real-time monitoring and removal of these harmful gases have emerged as significant challenges. In this work, the density functional theory (DFT) method was utilized to examine the adsorption behaviors and electronic properties of the Ni-decorated InSe (Ni-InSe) monolayer when interacting with twelve gases (CO, NO, NO2, NH3, SO2, H2S, H2O, CO2, CH4, H2, O2, and N2). A comparative assessment of adsorption strength and sensing properties was performed through analyses of the electronic structure, work function, and recovery time. The results show that Ni doping enhances the electrical conductivity of the InSe monolayer and improves the adsorption capabilities for six toxic gases (CO, NO, NO2, NH3, SO2, and H2S). Furthermore, the adsorption of these gases on the Ni-InSe surface is characterized as chemisorption, as indicated by the analysis of the adsorption energy, density of states, and charge density difference. Additionally, the adsorption of CO, NO, NO2, and SO2 results in significant alterations to the bandgap of Ni-InSe, with changes of 18.65%, 11.37%, 10.62%, and −31.77%, respectively, underscoring its exceptional sensitivity. Moreover, the Ni-InSe monolayer exhibits a moderate recovery time of 3.24 s at 298 K for the SO2. Consequently, the Ni-InSe is regarded as a promising gas sensor for detecting SO2 at room temperature. This research establishes a foundation for the development of an Ni-InSe-based gas sensor for detecting and mitigating harmful gas emissions. Full article
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12 pages, 4415 KiB  
Article
A Novel Mechanism Based on Oxygen Vacancies to Describe Isobutylene and Ammonia Sensing of p-Type Cr2O3 and Ti-Doped Cr2O3 Thin Films
by Pengfei Zhou, Jone-Him Tsang, Chris Blackman, Yanbai Shen, Jinsheng Liang, James A. Covington, John Saffell and Ehsan Danesh
Chemosensors 2024, 12(10), 218; https://doi.org/10.3390/chemosensors12100218 - 18 Oct 2024
Viewed by 700
Abstract
Gas sensors based on metal oxide semiconductors (MOS) have been widely used for the detection and monitoring of flammable and toxic gases. In this paper, p-type Cr2O3 and Ti-doped Cr2O3 (CTO) thin films were synthesized using an [...] Read more.
Gas sensors based on metal oxide semiconductors (MOS) have been widely used for the detection and monitoring of flammable and toxic gases. In this paper, p-type Cr2O3 and Ti-doped Cr2O3 (CTO) thin films were synthesized using an aerosol-assisted chemical vapor deposition (AACVD) method. Detailed analysis of the thin films deposited, including structural information, their elemental composition, oxidation state, and morphology, was investigated using XRD, Raman analysis, SEM, and XPS. All the gas sensors based on pristine Cr2O3 and CTO exhibited a reversible response and good sensitivity to isobutylene (C4H8) and ammonia (NH3) gases. Doping Ti into the Cr2O3 lattice improves the response of the CTO-based sensors to C4H8 and NH3. We describe a novel mechanism for the gas sensitivity of p-type metal oxides based on variations in the oxygen vacancy concentration. Full article
(This article belongs to the Special Issue Advanced Chemical Sensors for Gas Detection)
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18 pages, 1828 KiB  
Article
Tailoring Ruthenium(II) and Rhenium(I) Complexes for Turn-On Luminescent Sensing of Antimony(III)
by Alexandre Vieira Silva, Fabricio Ragone, Gustavo Teodosio Ruiz and Guillermo Orellana
Chemosensors 2024, 12(10), 217; https://doi.org/10.3390/chemosensors12100217 - 18 Oct 2024
Viewed by 733
Abstract
Antimony (Sb) is currently a widespread element with key roles in telecommunication, sustainable energy, and military industries, among others. Its significant toxicity determines the need to realize sensors for water, air, and soil and the industrial process monitoring of Sb species. Unfortunately, no [...] Read more.
Antimony (Sb) is currently a widespread element with key roles in telecommunication, sustainable energy, and military industries, among others. Its significant toxicity determines the need to realize sensors for water, air, and soil and the industrial process monitoring of Sb species. Unfortunately, no antimony sensors exist so far, and just laboratory analysis methods are in use. We aimed to contribute to the development of optical sensors for the metalloid by tailoring, for the first time, luminescent Ru(II) and Re(I) polypyridyl complexes to probe and quantify the presence of Sb(III). The molecular design of the complexes includes the multifunctional Sb-binding 2-(2,2′-bithien-5-yl)-1H-imidazo[4,5-f]-1,10-phenanthroline (btip) ligand that ensures the molecular binding of Sb(III) in organic media. The Ru(II)-btip complex is additionally endowed with one 2,2′-bipyrazine (bpz) or two 1,4,5,8-tetraazaphenanthrene (tap) ligands, namely [Ru(bpz)(btip)2]2+ and [Ru(tap)2(btip)]2+, that boost the excited state oxidation potential of the probe, leading to an intramolecular photoinduced electron transfer from btip to the Ru(II) core. The latter is suppressed upon interaction with Sb(III), leading to an 11-fold increase in both the luminescence intensity and lifetime of [Ru(bpz)(btip)2]2+ in the presence of ca. 50 μmol L−1 of SbCl3 in organic medium. The fluorescence intensity of [Re(CO)3(H2O)(btip)]+ also increases upon interaction with Sb(III) but to a much lesser extent due to the intraligand π*→π nature of its emission compared to the Ru(II) ligand-to-metal excited state deactivation. However, the weak π*→d emission band in the red spectral region of the former is quenched by the semimetallic element. The sensing mechanisms of the Ru(II)- and Re(I)-btip probes that allow luminescence intensity (Ru, Re), ratiometric (Ru), and lifetime measurements (Ru) are compared and discussed in this initial solution sensing study. Full article
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10 pages, 1926 KiB  
Communication
Construction of a Miniaturized Detector for Flow Injection Spectrophotometric Analysis
by T. Alexandra Ferreira, Mario Ordaz, Jose A. Rodriguez, M. Elena Paez-Hernandez and Evelin Gutierrez
Chemosensors 2024, 12(10), 216; https://doi.org/10.3390/chemosensors12100216 - 17 Oct 2024
Viewed by 545
Abstract
Analytical instrumentation is essential for chemical analysis in many fields, including biology and chemistry, but it can be costly and inaccessible to many educational institutions because it often requires expensive and sophisticated equipment. To address this issue, there has been growing interest in [...] Read more.
Analytical instrumentation is essential for chemical analysis in many fields, including biology and chemistry, but it can be costly and inaccessible to many educational institutions because it often requires expensive and sophisticated equipment. To address this issue, there has been growing interest in developing new and accessible alternatives. In this study, we developed a low-cost and user-friendly spectrophotometric detector based on an Arduino UNO platform. This detector was coupled with a flow injection analysis system (FIA) and used to quantify the concentration of tartrazine in commercial beverages and candy samples. The proposed miniaturized detector offers an affordable and portable alternative to conventional spectrophotometers. We evaluated the performance of our detector by comparing its results with those obtained using high-performance liquid chromatography (HPLC-DAD), and the accuracy and precision were comparable. The results demonstrate the potential of the Arduino-based spectrophotometric detector as a cost-effective and accessible tool, with potential applications in food science, environmental monitoring, and other fields. Full article
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19 pages, 3472 KiB  
Article
Electrochemical DNA Sensor Based on Poly(proflavine) Deposited from Natural Deep Eutectic Solvents for DNA Damage Detection and Antioxidant Influence Assessment
by Anna Porfireva, Anastasia Goida, Vladimir Evtugyn, Milena Mozgovaya, Tatiana Krasnova and Gennady Evtugyn
Chemosensors 2024, 12(10), 215; https://doi.org/10.3390/chemosensors12100215 - 16 Oct 2024
Viewed by 832
Abstract
Electrochemical DNA sensors for DNA damage detection based on electroactive polymer poly(proflavine) (PPFL) that was synthesized at screen-printed carbon electrodes (SPCEs) from phosphate buffer (PB) and two natural deep eutectic solvents (NADESs) consisting of citric or malonic acids, D-glucose, and a certain amount [...] Read more.
Electrochemical DNA sensors for DNA damage detection based on electroactive polymer poly(proflavine) (PPFL) that was synthesized at screen-printed carbon electrodes (SPCEs) from phosphate buffer (PB) and two natural deep eutectic solvents (NADESs) consisting of citric or malonic acids, D-glucose, and a certain amount of water (NADES1 and NADES2) were developed. Poly(proflavine) coatings obtained from the presented media (PPFLPB, PPFLNADES1, and PPFLNADES2) were electrochemically polymerized via the multiple cycling of the potential or potentiostatic accumulation and used for the discrimination of thermal and oxidative DNA damage. The electrochemical characteristics of the poly(proflavine) coatings and their morphology were assessed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). The working conditions for calf thymus DNA implementation and DNA damage detection were estimated for all types of poly(proflavine) coatings. The voltammetric approach made it possible to distinguish native and chemically oxidized DNA while the impedimetric approach allowed for the successful recognition of native, thermally denatured, and chemically oxidized DNA through changes in the charge transfer resistance. The influence of different concentrations of conventional antioxidants and pharmaceutical preparations on oxidative DNA damage was characterized. Full article
(This article belongs to the Special Issue Electrochemical Biosensors: Advances and Prospects)
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12 pages, 4553 KiB  
Article
A Biomimetic Chip with Dendrimer-Encapsulated Platinum Nanoparticles for Enhanced Electrochemiluminescence Detection of Cardiac Troponin I
by Yun Hui, Weijun Kong, Weiliang Shu, Zhiting Peng, Fengshan Shen, Mingyang Jiang, Zhen Xu, Tianzhun Wu, Wenhua Zhou and Xue-Feng Yu
Chemosensors 2024, 12(10), 214; https://doi.org/10.3390/chemosensors12100214 - 16 Oct 2024
Viewed by 618
Abstract
The measurement of cardiac troponin I (cTnI) is of vital importance for the early diagnosis of acute myocardial infarction. In this study, an enhanced electrochemiluminescent immunoassay for the highly sensitive and precise determination of cTnI was reported. A biomimetic chip with nepenthes peristome [...] Read more.
The measurement of cardiac troponin I (cTnI) is of vital importance for the early diagnosis of acute myocardial infarction. In this study, an enhanced electrochemiluminescent immunoassay for the highly sensitive and precise determination of cTnI was reported. A biomimetic chip with nepenthes peristome surface microstructures to achieve single-layer microbead arrays and integrated microelectrode arrays (MEAs) for ECL detection was microfabricated. Ru@SiO2 nanoparticles were prepared as signal amplificators labeling immunomagnetic beads. Dendrimer-encapsulated platinum nanoparticles (Pt DENs) were electrochemically modified on ITO MEAs. The resulting Pt DEN-modified ITO MEAs preserved good optical transparency and exhibited an approximately 20-fold ECL signal amplification compared to that obtained from bare ITO. The method made full use of the biomimetic chip with Pt DENs to develop single-layer immunomagnetic bead arrays with increasingly catalyzed electrochemical oxidation of the [Ru(bpy)3]2+–TPA system. Consequently, a limit of detection calculated as 0.38 pg/mL (S/N = 3) was obtained with excellent selectivity, demonstrating significant potential for the detection of cTnI in clinical diagnostics. Full article
(This article belongs to the Special Issue Application of Luminescent Materials for Sensing, 2nd Edition)
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13 pages, 3257 KiB  
Article
SERS-Driven Ceftriaxone Detection in Blood Plasma: A Protein Precipitation Approach
by Aradhana Dwivedi, Oleg Ryabchykov, Chen Liu, Edoardo Farnesi, Michael Stenbæk Schmidt, Thomas Bocklitz, Jürgen Popp and Dana Cialla-May
Chemosensors 2024, 12(10), 213; https://doi.org/10.3390/chemosensors12100213 - 16 Oct 2024
Viewed by 731
Abstract
Accurate detection of antibiotics in biological samples is essential for clinical diagnoses and therapeutic drug monitoring. This research examines how proteins and other substances in blood plasma affect the detection of the antibiotic ceftriaxone using surface-enhanced Raman spectroscopy (SERS). We detected ceftriaxone spiked [...] Read more.
Accurate detection of antibiotics in biological samples is essential for clinical diagnoses and therapeutic drug monitoring. This research examines how proteins and other substances in blood plasma affect the detection of the antibiotic ceftriaxone using surface-enhanced Raman spectroscopy (SERS). We detected ceftriaxone spiked in blood plasma without sample preparation within the range of 1 mg/mL to 50 µg/mL. By employing a pretreatment approach involving methanol-based protein precipitation to eliminate interfering substances from a spiked blood plasma solution, we could detect ceftriaxone down to 20 µg/mL. The comparative analysis demonstrates that the protein precipitation step enhances the sensitivity of SERS-based detection of drugs in the matrix blood plasma. The insights derived from this study are highly beneficial and can prove advantageous in developing new antibiotic detection methods that are both sensitive and selective in complex biological matrices. These methods can have important implications for clinical treatments. Full article
(This article belongs to the Special Issue Surface-Enhanced Raman Spectroscopy for Bioanalytics)
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14 pages, 4109 KiB  
Article
The Influence of Temperature on the Spatial Distribution of AuNPs on a Ceramic Substrate for Biosensing Applications
by Yazmín Mariela Hernández-Rodríguez, Esperanza Baños-López, Pablo Damián-Matsumura, Claudia Haydée González de la Rosa and Oscar Eduardo Cigarroa-Mayorga
Chemosensors 2024, 12(10), 212; https://doi.org/10.3390/chemosensors12100212 - 15 Oct 2024
Viewed by 857
Abstract
In this study, we investigated the spatial distribution and homogeneity of gold nanoparticles (AuNPs) on an alumina (Al2O3; AAO) substrate for potential application as surface-enhanced Raman scattering (SERS) sensors. The AuNPs were synthesized through thermal treatment at 450 °C [...] Read more.
In this study, we investigated the spatial distribution and homogeneity of gold nanoparticles (AuNPs) on an alumina (Al2O3; AAO) substrate for potential application as surface-enhanced Raman scattering (SERS) sensors. The AuNPs were synthesized through thermal treatment at 450 °C at varying times (5, 15, 30, and 60 min), and their distribution was characterized using field-emission scanning electron microscopy (FE-SEM) and scanning transmission electron microscopy (STEM). The FE-SEM and STEM analyses revealed that the size and interparticle distance of the AuNPs were significantly influenced by the duration of thermal treatment, with shorter times promoting smaller and more closely spaced nanoparticles, and longer times resulting in larger and more dispersed particles. Raman spectroscopy, using Rhodamine 6G (R6G) as a probe molecule, was employed to evaluate the SERS enhancement provided by the AuNPs on the AAO substrate. Raman mapping (5 µm × 5 µm) was conducted on five sections of each sample, demonstrating improved homogeneity in the SERS effect across the substrate. The topological features of the AuNPs before and after R6G incubation were analyzed using atomic force microscopy (AFM), confirming the correlation between a decrease in surface roughness and an increase in R6G adsorption. The reproducibility of the SERS effect was quantified using the maximum intensity deviation (D), which was found to be below 20% for all samples, indicating good reproducibility. Among the tested conditions, the sample synthesized for 15 min exhibited the most favorable characteristics, with the smallest average nanoparticle size and interparticle distance, as well as the most consistent SERS enhancement. These findings suggest that AuNPs on AAO substrates, particularly those synthesized under the optimized condition of 15 min at 450 °C, are promising candidates for use in SERS-based sensors for detecting cancer biomarkers. This could be attributed to temperature propagation promoted at the time of synthesis. The results also provide insights into the influence of thermal treatment on the spatial distribution of AuNPs and their subsequent impact on SERS performance. Full article
(This article belongs to the Special Issue Biochemical Sensors Using Nanotechnology)
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18 pages, 4783 KiB  
Article
The Bray–Liebhafsky Oscillatory Reaction as a Chemosensor for Benzenediols
by Aleksandra Pavićević, Marija Veles, Jelena Maksimović, Jelena Tošović, Urban Bren, Uroš Čakar and Maja Pagnacco
Chemosensors 2024, 12(10), 211; https://doi.org/10.3390/chemosensors12100211 - 15 Oct 2024
Viewed by 716
Abstract
Benezediols are widely used in different areas of industry, thus identification and quantification of benzenediols is of utmost importance due to their toxicity and high environmental abundance. In this work, benzenediol isomers (pyrocatechol, resorcinol, and hydroquinone) were investigated by using the Bray–Liebhafsky (BL) [...] Read more.
Benezediols are widely used in different areas of industry, thus identification and quantification of benzenediols is of utmost importance due to their toxicity and high environmental abundance. In this work, benzenediol isomers (pyrocatechol, resorcinol, and hydroquinone) were investigated by using the Bray–Liebhafsky (BL) oscillatory reaction. All three isomers exhibit different behavior in the BL reaction, which renders the BL system applicable as a chemosensor. The period between the fifth and sixth oscillation, the amplitude of the sixth oscillation and in the case of hydroquinone, the emergence of a new oscillation in the BL reaction were selected as the parameters used for the identification and quantification of these isomers. Furthermore, electron paramagnetic resonance spectroscopy and DFT calculations were performed in order to provide insights into the mechanism of benzenediols reactions with the BL system. Full article
(This article belongs to the Section Analytical Methods, Instrumentation and Miniaturization)
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16 pages, 8860 KiB  
Article
Lithium Niobate Perovskite as the Support for Silver Nanoparticles for Non-Enzymatic Electrochemical Detection of Glucose
by Claudia Ivone Piñón-Balderrama, Atenea Manríquez-Tristán, María Cristina Maldonado-Orozco, Claudia Alejandra Hernández-Escobar, Simón Yobanny Reyes-López, León Francisco Espinosa-Cristobal and Erasto Armando Zaragoza-Contreras
Chemosensors 2024, 12(10), 210; https://doi.org/10.3390/chemosensors12100210 - 15 Oct 2024
Viewed by 752
Abstract
Lithium niobate perovskite and silver nanoparticle-based nanocomposites (LNB:AgNPs) were explored for developing an electrochemical glucose sensor. The perovskite to silver nanoparticle ratios investigated were 4:1, 1:1, 1:2, 2:1, and 1:4. Among these, the 4:1 ratio, with the lowest silver content, demonstrated the most [...] Read more.
Lithium niobate perovskite and silver nanoparticle-based nanocomposites (LNB:AgNPs) were explored for developing an electrochemical glucose sensor. The perovskite to silver nanoparticle ratios investigated were 4:1, 1:1, 1:2, 2:1, and 1:4. Among these, the 4:1 ratio, with the lowest silver content, demonstrated the most stable performance during glucose quantification via amperometry. The sensor’s response was evaluated measuring the current at a fixed potential of 0.7 V following the injection of 1 mM glucose with each addition. The calibration curve obtained from the recorded data exhibited a linear response within the 1 to 15 mM glucose concentration range, achieving a sensitivity of 2 μA/mM, a high correlation coefficient (R2 = 0.997), and a limit of detection (LOD) of 0.5 µM. The LNB4:1AgNP composite allowed taking advantage of the unique properties of both components in a balanced manner, maximizing the sensor performance in practical applications. Full article
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18 pages, 29362 KiB  
Review
Advancements and Applications of Single-Atom Nanozymes in Sensing Analysis
by Huiyun Zhang, Shouting Zhang and Zhicheng Zhang
Chemosensors 2024, 12(10), 209; https://doi.org/10.3390/chemosensors12100209 - 12 Oct 2024
Viewed by 556
Abstract
Single-atom nanozymes, with their atomically dispersed metal active sites, distinctive atom utilization rate, and tunable electronic structure, demonstrate great promise in the field of sensing analysis. This paper reviews the latest research progress on single-atom nanozymes in sensing applications. We classify single-atom nanozymes [...] Read more.
Single-atom nanozymes, with their atomically dispersed metal active sites, distinctive atom utilization rate, and tunable electronic structure, demonstrate great promise in the field of sensing analysis. This paper reviews the latest research progress on single-atom nanozymes in sensing applications. We classify single-atom nanozymes based on both their structural characteristics, such as carbon-based carriers, frameworks and their derivatives, metal oxides, metal sulfides, and organic polymer carriers, and their unique catalytic properties, including peroxidase, oxidase, catalase, superoxide dismutase, and multi-enzyme mimetic activities. Furthermore, we discuss the application of single-atom nanozymes in the sensitive detection of biological small molecules, antioxidants, ions, enzyme activities and their inhibitors, as well as cells and viruses. Finally, we highlight the opportunities and challenges for advancing the practical application and further research of single-atom nanozymes in the field of sensing analysis. Full article
(This article belongs to the Special Issue Nanozyme-Enabled Analytical Chemistry)
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15 pages, 4857 KiB  
Article
Paper-Based Analytical Devices Based on Amino-MOFs (MIL-125, UiO-66, and MIL-101) as Platforms towards Fluorescence Biodetection Applications
by Sofía V. Piguillem, Germán E. Gomez, Gonzalo R. Tortella, Amedea B. Seabra, Matías D. Regiart, Germán A. Messina and Martín A. Fernández-Baldo
Chemosensors 2024, 12(10), 208; https://doi.org/10.3390/chemosensors12100208 - 11 Oct 2024
Viewed by 862
Abstract
In this study, we designed three promising platforms based on metal–organic frameworks (MOFs) to develop paper-based analytical devices (PADs) for biosensing applications. PADs have become increasingly popular in field sensing in recent years due to their portability, low cost, simplicity, efficiency, fast detection [...] Read more.
In this study, we designed three promising platforms based on metal–organic frameworks (MOFs) to develop paper-based analytical devices (PADs) for biosensing applications. PADs have become increasingly popular in field sensing in recent years due to their portability, low cost, simplicity, efficiency, fast detection capability, excellent sensitivity, and selectivity. In addition, MOFs are excellent choices for developing highly sensitive and selective sensors due their versatility for functionalizing, structural stability, and capability to adsorb and desorb specific molecules by reversible interactions. These materials also offer the possibility to modify their structure and properties, making them highly versatile and adaptable to different environments and sensing needs. In this research, we synthesized and characterized three different amino-functionalized MOFs: UiO-66-NH2 (Zr), MIL-125-NH2 (Ti), and MIL-101-NH2 (Fe). These MOFs were used to fabricate PADs capable of sensitive and portable monitoring of alkaline phosphatase (ALP) enzyme activity by laser-induced fluorescence (LIF). Overall, amino-derivated MOF platforms demonstrate significant potential for integration into biosensor PADs, offering key properties that enhance their performance and applicability in analytical chemistry and diagnostics. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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11 pages, 3509 KiB  
Article
Quantitative Chemical Sensing Using Genetically Engineered Bacterial Bioreporters
by Yonatan Uziel, Yossef Kabessa, Benjamin Shemer, Etai Shpigel, Shimshon Belkin and Aharon J. Agranat
Chemosensors 2024, 12(10), 207; https://doi.org/10.3390/chemosensors12100207 - 11 Oct 2024
Viewed by 669
Abstract
We present a generic quantitative chemical sensing methodology for assessing the concentration of a target material (TM) in an aqueous solution by using bioluminescent microbial bioreporters as the core sensing elements. Such bioreporters, genetically engineered to respond to the presence of a TM [...] Read more.
We present a generic quantitative chemical sensing methodology for assessing the concentration of a target material (TM) in an aqueous solution by using bioluminescent microbial bioreporters as the core sensing elements. Such bioreporters, genetically engineered to respond to the presence of a TM in their microenvironment by emitting bioluminescence, have previously been mostly designed to report the presence or absence of the TM in the sample. We extend this methodology to also assess the TM concentration, by exploiting the dose-dependency of the TM-induced luminescence. To overcome luminescence intensity variations due to bacterial batch differences and the ambient temperature, simultaneous measurements were carried out on sample solutions containing known concentrations of the TM. A “standard ratio” parameter, defined as the ratio between the two measurements, is shown to be independent of the bacterial batch and the temperature, and hence provides the conceptual basis for a generic quantitative chemical sensing methodology. Assessment of 2,4-dinitrotoluene (DNT) concentration in solutions is demonstrated with an accuracy of 2.5% over a wide dynamic range. Full article
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16 pages, 3414 KiB  
Article
Green and Sensitive Analysis of the Antihistaminic Drug Pheniramine Maleate and Its Main Toxic Impurity Using UPLC and TLC Methods, Blueness Assessment, and Greenness Assessments
by Nessreen S. Abdelhamid, Huda Salem AlSalem, Faisal K. Algethami, Eglal A. Abdelaleem, Alaa M. Mahmoud, Dalal A. Abou El Ella and Mohammed Gamal
Chemosensors 2024, 12(10), 206; https://doi.org/10.3390/chemosensors12100206 - 9 Oct 2024
Viewed by 605
Abstract
For the first time, two direct and eco-friendly chromatographic approaches were adapted for the simultaneous estimation of pheniramine maleate (PAM) and its major toxic impurity, 2-benzyl pyridine (BNZ). Method A used reversed-phase ultra-performance liquid chromatography; separation was achieved within 4 min using a [...] Read more.
For the first time, two direct and eco-friendly chromatographic approaches were adapted for the simultaneous estimation of pheniramine maleate (PAM) and its major toxic impurity, 2-benzyl pyridine (BNZ). Method A used reversed-phase ultra-performance liquid chromatography; separation was achieved within 4 min using a C18 column with a developing system of methanol/water (60:40 v/v) with a 0.1 mL/min flow rate. Photodiode array detection was adjusted at 215 nm. The method was linear in the ranges of 5.0–70.0 and 0.05–10.0 µg/mL for PAM and BNZ, correspondingly. Method B used thin-layer chromatography; separation was applied on silica gel TLC F254 using ethanol/ethyl acetate/liquid ammonia (8:2:0.1, in volumes) at room temperature, at 265 nm. Linearity was assured at concentration ranges 0.5–8.0 and 0.1–3.0 µg/band for the two components, respectively. Generally, the new UPLC and TLC methods outperform the old ones in terms of quickness, greenness, and sensitivity. Concisely, the greenness features were partially achieved using the Green Analytical Procedure Index (GAPI) and the Analytical Greenness (AGREE) pictograms. In contrast, the usefulness of the novel approaches was assured via the Blue Applicability Grade Index (BAGI) tool. Full article
(This article belongs to the Special Issue Green Analytical Chemistry: Current Trends and Future Developments)
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14 pages, 3066 KiB  
Article
Coffee Biomass-Based Carbon Material for the Electrochemical Determination of Antidepressant in Synthetic Urine
by Francisco Contini Barreto, Naelle Kita Mounienguet, Erika Yukie Ito, Quan He and Ivana Cesarino
Chemosensors 2024, 12(10), 205; https://doi.org/10.3390/chemosensors12100205 - 3 Oct 2024
Viewed by 891
Abstract
Escitalopram (ESC) is commonly prescribed as an antidepressant to enhance serotonin levels in the brain, effectively addressing conditions such as depression and anxiety. The COVID-19 pandemic, along with ongoing mental health crises, has exacerbated the prevalence of these disorders, largely due to factors [...] Read more.
Escitalopram (ESC) is commonly prescribed as an antidepressant to enhance serotonin levels in the brain, effectively addressing conditions such as depression and anxiety. The COVID-19 pandemic, along with ongoing mental health crises, has exacerbated the prevalence of these disorders, largely due to factors such as social isolation, fear of the virus, and financial difficulties. This study presents the enhancement of a glassy carbon electrode (GC) through the incorporation of hydrochar (HDC) derived from spent coffee grounds and copper nanoparticles (CuNPs) for the detection of ESC in synthetic urine. Characterization of the nanocomposite was conducted using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and cyclic voltammetry (CV). The analytical parameters were systematically optimized, and a sensing platform was utilized for the quantification of ESC via square-wave voltammetry (SWV). The established linear range was found to be between 1.0 µmol L−1 and 50.0 µmol L−1, with a limit of detection (LOD) of 0.23 µmol L−1. Finally, an electrochemical sensor was employed to measure ESC levels in synthetic urine, yielding recovery rates ranging from 91.7% to 94.3%. Consequently, the HDC-CuNPs composite emerged as a promising, sustainable, and cost-effective alternative for electroanalytical applications. Full article
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15 pages, 2655 KiB  
Article
Correlation of Plasma Temperature in Laser-Induced Breakdown Spectroscopy with the Hydrophobic Properties of Silicone Rubber Insulators
by Olga Kokkinaki, Panagiotis Siozos, Nikolaos Mavrikakis, Kiriakos Siderakis, Kyriakos Mouratis, Emmanuel Koudoumas, Ioannis Liontos, Kostas Hatzigiannakis and Demetrios Anglos
Chemosensors 2024, 12(10), 204; https://doi.org/10.3390/chemosensors12100204 - 3 Oct 2024
Viewed by 893
Abstract
In this study, we have investigated the relationship between the plasma temperature in remote laser-induced breakdown spectroscopy (LIBS) experiments and the hydrophobic properties of silicone rubber insulators (SIRs). Contact angle and LIBS measurements were conducted on both artificially-aged (accelerated aging) and field-aged SIRs. [...] Read more.
In this study, we have investigated the relationship between the plasma temperature in remote laser-induced breakdown spectroscopy (LIBS) experiments and the hydrophobic properties of silicone rubber insulators (SIRs). Contact angle and LIBS measurements were conducted on both artificially-aged (accelerated aging) and field-aged SIRs. This study reveals a clear connection between plasma temperature and the properties of aged SIRs on artificially-aged SIR specimens. Specifically, the plasma temperature exhibits a consistent increase with the duration of the accelerated aging test. The hydrophobicity of the artificially-aged SIRs was assessed by performing contact angle measurements, revealing a decrease in the hydrophobicity with increased aging test duration. Furthermore, we extended our investigation to the study of nine field-aged SIRs that had been in use on 150 kV overhead transmission lines for 0 to 21 years. We find that the laser absorption and hardness of the material do not relate to the plasma temperature. In summary, we observe a direct connection of plasma temperature to both contact-angle measurements and operation time of the in-service insulators. These results strongly suggest the potential use of LIBS for remotely evaluating the hydrophobicity and aging degree of silicone rubber insulators, thus assessing their real-time on-site operational quality. Full article
(This article belongs to the Special Issue Application of Laser-Induced Breakdown Spectroscopy, 2nd Edition)
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12 pages, 2670 KiB  
Article
A Zinc Oxide Nanorod-Based Electrochemical Aptasensor for the Detection of Tumor Markers in Saliva
by Junrong Li, Yihao Ding, Yuxuan Shi, Zhiying Liu, Jun Lin, Rui Cao, Miaomiao Wang, Yushuo Tan, Xiaolin Zong, Zhan Qu, Liping Du and Chunsheng Wu
Chemosensors 2024, 12(10), 203; https://doi.org/10.3390/chemosensors12100203 - 2 Oct 2024
Viewed by 735
Abstract
Biosensors have emerged as a promising tool for the early detection of oral squamous cell carcinoma (OSCC) due to their rapid, sensitive, and specific detection of cancer biomarkers. Saliva is a non-invasive and easy-to-obtain biofluid that contains various biomarkers of OSCC, including the [...] Read more.
Biosensors have emerged as a promising tool for the early detection of oral squamous cell carcinoma (OSCC) due to their rapid, sensitive, and specific detection of cancer biomarkers. Saliva is a non-invasive and easy-to-obtain biofluid that contains various biomarkers of OSCC, including the carcinoembryonic antigen (CEA). In this study, an electrochemical aptasensor for the detection of CEA in saliva has been developed towards the diagnosis and early screening of OSCC. This aptasensor utilized a CEA-sensitive aptamer as sensitive elements. A fluorine-doped Tin Oxide (FTO) chip with a surface modification of a zinc oxide nanorod was employed as a transducer. Electrochemical measurements were carried out to detect the responsive signals originating from the specific binding between aptamers and CEAs. The measurement results indicated that this aptasensor was responsive to different concentrations of CEA ranging from 1 ng/mL to 80 ng/mL in a linear relationship. The limit of detection (LOD) was 0.75 ng/mL. This aptasensor also showed very good specificity and regenerative capability. Stability testing over a 12-day period showed excellent performance of this aptasensor. All the results demonstrated that this aptasensor has great potential to be used for the detection of CEA in the saliva of OSCC patients. This aptasensor provides a promising method for the rapid detection of CEA with convenience, which has great potential to be used as a new method for clinical diagnoses and early screening of OSCC. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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11 pages, 1357 KiB  
Article
Application of a Novel Disposable Flow Cell for Spectroscopic Bioprocess Monitoring
by Tobias Steinwedel, Philipp Raithel, Jana Schellenberg, Carlotta Kortmann, Pia Gellermann, Mathias Belz and Dörte Solle
Chemosensors 2024, 12(10), 202; https://doi.org/10.3390/chemosensors12100202 - 1 Oct 2024
Cited by 1 | Viewed by 750
Abstract
The evaluation of the analytical capabilities of a novel disposable flow cell for spectroscopic bioprocess monitoring is presented. The flow cell is presterilized and can be connected to any kind of bioreactor by weldable tube connections. It is clamped into a reusable holder, [...] Read more.
The evaluation of the analytical capabilities of a novel disposable flow cell for spectroscopic bioprocess monitoring is presented. The flow cell is presterilized and can be connected to any kind of bioreactor by weldable tube connections. It is clamped into a reusable holder, which is equipped with SMA-terminated optical fibers or an integrated light source and detection unit. This modular construction enables spectroscopic techniques like UV-Vis spectroscopy or turbidity measurements by scattered light for modern disposable bioreactors. A NIR scattering module was used for biomass monitoring in different cultivations. A high-cell-density fed-batch cultivation with Komagataella phaffii and a continuous perfusion cultivation with a CHO DG44 cell line were conducted. A high correlation between the sensor signal and biomass or viable cell count was observed. Furthermore, the sensor shows high sensitivity during low turbidity states, as well as a high dynamic range to monitor high turbidity values without saturation effects. In addition to upstream processing, the sensor system was used to monitor the purification process of a monoclonal antibody. The absorption module enables simple and cost-efficient monitoring of downstream processing and quality control measurements. Recorded absorption spectra can be used for antibody aggregate detection, due to an increase in overall optical density. Full article
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11 pages, 2977 KiB  
Article
A Fluorescence Strategy Based on Guanidinylated Carbon Dots and FAM-Labeled ssDNA for Facile Detection of Lipopolysaccharide
by Zongfu Zheng, Junrong Li, Gengping Pan, Jing Wang, Yao Wang, Kai Peng, Xintian Zhang, Zhengjun Huang and Shaohuang Weng
Chemosensors 2024, 12(10), 201; https://doi.org/10.3390/chemosensors12100201 - 1 Oct 2024
Viewed by 589
Abstract
The detection of lipopolysaccharide (LPS) has important value for the monitoring of diseases such as sepsis and the impurity control of drugs. In this work, we prepared guanidinylated carbon dots (GQ-CDs) and used them to adsorb 5-carboxyfluorescein (FAM)-labeled single-stranded DNA (ssDNA) to become [...] Read more.
The detection of lipopolysaccharide (LPS) has important value for the monitoring of diseases such as sepsis and the impurity control of drugs. In this work, we prepared guanidinylated carbon dots (GQ-CDs) and used them to adsorb 5-carboxyfluorescein (FAM)-labeled single-stranded DNA (ssDNA) to become GQ-CDs/FAM-DNA, resulting in quenched FAM. The quenching efficiency of the FAM-DNA by GQ-CDs in the GQ-CDs/FAM-DNA system was 91.95%, and this quenching was stable over the long term. Upon the addition of LPS, the quenched FAM-DNA in the GQ-CDs/FAM-DNA system regained fluorescence at 520 nm. The mechanism studies found that the addition of LPS promoted the dissociation of FAM-DNA adsorbed on GQ-CDs, thereby restoring fluorescence. The degree of fluorescence recovery was closely related to the content of LPS. Under optimized conditions, the fluorescence recovery was linearly related to LPS concentrations ranging from 5 to 90 μg/mL, with a detection limit of 0.75 μg/mL. The application of this method to plasma samples and trastuzumab injections demonstrated good spiked recoveries and reproducibility. This platform, based on GQ-CDs for the adsorption and quenching of FAM-DNA, enables the detection of LPS through relatively simple mixing operations, showing excellent competitiveness for the determination of actual samples under various conditions. Full article
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10 pages, 3164 KiB  
Article
Assessment of Optical and Scanning Electron Microscopies for the Identification and Quantification of Asbestos Fibers and Typical Asbestos Bodies in Human Colorectal Cancer Tissues
by Alessandro Croce, Marinella Bertolotti, Donata Bellis, Alex Glorioso, Carlotta Bertolina, Marianna Farotto, Fabio Giacchero, Annalisa Roveta and Antonio Maconi
Chemosensors 2024, 12(10), 200; https://doi.org/10.3390/chemosensors12100200 - 1 Oct 2024
Viewed by 806
Abstract
Asbestos research, identification, and quantification have been performed over the years, and the relationship between fiber inhalation and lung disease development is well defined. The same cannot be said for the gastroenteric system: the International Agency for Research on Cancer (IARC) believes that [...] Read more.
Asbestos research, identification, and quantification have been performed over the years, and the relationship between fiber inhalation and lung disease development is well defined. The same cannot be said for the gastroenteric system: the International Agency for Research on Cancer (IARC) believes that colorectal cancer (CRC) could be associated with asbestos exposure, but research has not demonstrated a casual nexus between exposure and CRC, despite highlighting an association tendency. The combination of scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) is the most applied technique in asbestos fiber identification in tissues and intestinal mucosa. In this study, SEM/EDS was applied to evaluate the presence of asbestos fibers and bodies (ABs) inside the tissue of eleven patients affected by CRC who had undergone environmental exposure due to living in an asbestos-polluted area where an Eternit plant had been active in the past. This technique was coupled with optical microscopy (OM) to verify whether the latter could be applied to evaluate the presence of these mineral phases, with the goal of understanding its suitability for identifying fibers and ABs in colon tissues. In addition to verifying the presence of fibers, this study allowed us to identify the deposition site of said fibers within the sample and possibly detect associated tissue reactions using OM, over a shorter time and at lower costs. Despite being a preliminary and descriptive work, the obtained results allowed us to propose a method involving first-sample OM observation to identify regulated (fibers with a length ≥ 5 μm, a thickness ≤ 3 μm, and a length/thickness ratio > 3) asbestos phases and ABs in the extra-respiratory system. In fact, OM and SEM/EDS provided similar information: no asbestiform morphology or ABs were found, but phyllosilicates and other inorganic materials were identified. This research needs to be continued using higher-resolution techniques to definitively rule out the presence of these fibers inside tissues whilst also increasing the number of patients involved. Full article
(This article belongs to the Section Imaging for (Bio)chemical Sensing)
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