Search Results (826)

The development of reliable electrochemical interfaces for biosensor applications requires materials that combine high conductivity, large effective surface area, and suitable platforms for biomolecule immobilization. In this work, a hybrid electrochemical platform based on screen-printed carbon electrodes (SPCEs) modified with electropolymerized polypyrrole (PPy) and electrodeposited silver particles (AgPs) is presented for the subsequent immobilization of Ki-67 antibodies. PPy films were synthesized under optimized electrochemical conditions, producing homogeneous, porous, and electrochemically stable coatings that significantly enhanced the doping/undoping processes from 0.3280 C/0.3284 C to 0.3281 C/0.3284 C for SPCE and SPCE-PPy, respectively. Subsequently, silver particles were deposited onto the PPy matrix, resulting in a well-dispersed and uniform distribution of AgPs, promoted by the interaction between Ag⁰ and the nitrogen groups in the polymer backbone. The synergistic combination of PPy and AgPs resulted in improved charge-transfer properties and enhanced electrochemical reversibility, thereby decreasing the peak-to-peak separation of the ferricyanide/ferrocyanide redox couple used as a probe by 40%. Immobilization of Ki-67 antibodies was achieved via direct interaction with AgPs, resulting in a marked passivation effect, as evidenced by the suppression of redox probe signals, confirming successful biofunctionalization. The proposed SPCE-PPy-AgP architecture provides a robust, reproducible, and versatile platform for antibody immobilization, as demonstrated by oxidation and reduction peaks with relative standard deviations (RSDs) of 3.18% and 4.43%, respectively, highlighting its potential for developing label-free electrochemical immunosensors for clinically relevant proliferation biomarkers. Full article

Kombucha, a traditionally fermented tea, has gained increasing scientific and commercial interest due to its sensory quality and bioactive metabolites profile associated with different health-related activities. Recent research highlights the value of enriching traditional and honey kombucha with plant-based biomolecules to create new functional beverages with enhanced functional and nutraceutical properties, improved flavor, and chemical stability. Therefore, this study aimed to review and update the research on the enrichment of kombucha with these natural biomolecules that have been shown to expand the spectrum of health-promoting activities (e.g., antioxidant, antimicrobial, anticancer, and anti-aging), while also enhancing the physicochemical stability of raw kombucha. Yet this innovation must be navigated with a thoughtful understanding of safety, biochemical stability, and sensory evaluation. Thus, this review strongly advocates that the integrative enrichment approach presents a promising strategy for developing next-generation functional beverages with synergistic nutritional and therapeutic benefits. Further controlled studies are needed to elucidate the mechanistic interactions between the kombucha’s microbiome and these added bioactive substrates, as well as to optimize formulations for targeted health applications. Full article

The study of volatile organic compounds (VOCs)-mediated plant growth promotion has long focused on various beneficial microbial species. As an important natural source of functional biomolecules, the biological function and potential value of VOCs released by plant pathogenic fungi in regulating plant growth still lack sufficient research, and further exploration is needed. In this study, a phytopathogenic fungus Alternaria alstroemeriae (strain Z84) was isolated from Vaccinium dunalianum for the first time, and the effects of its VOCs on the growth of Arabidopsis thaliana and Nicotiana benthamiana were systematically investigated. The results showed that after Z84 VOCs treatment, multiple phenotypic traits of the two plants were significantly improved, and the chlorophyll content was also markedly increased. Transcriptome analysis showed that a total of 1401 differentially expressed genes (DEGs) were identified in the treated A. thaliana, of which 629 were up-regulated and 772 were down-regulated. KEGG enrichment analysis showed that these DEGs were mainly enriched in photosynthesis-antenna proteins, plant–pathogen interaction, glutathione metabolism, plant hormone signal transduction, flavonoid biosynthesis and photosynthesis-related pathways. Metabolomics analysis revealed that Z84 VOCs treatment significantly changed the metabolic profile of A. thaliana, with the most significant changes in amino acid metabolism-related pathways. It is noteworthy that the plant hormone spectrum of A. thaliana was significantly changed after treatment, and the contents of salicylic acid (SA), abscisic acid (ABA) and gibberellins (GAs) were significantly up-regulated. These results not only demonstrate the potential of Z84-derived VOCs to facilitate plant growth but also provide an important basis for further dissecting the molecular mechanisms of plant–pathogenic fungi interactions. Full article

Background: Heterocycle compounds with acridine, quinoline, indole, and pyridine nuclei are potentially active for anticancer activity since they can promote inhibition of vital enzymes, decreasing cell survival after binding to biomolecules. However, unspecific biological interactions can result in unwanted effects, which should be defined during the synthesis and proposition of new molecules. Thus, the objective of this study was to investigate the biological and teratogenic effects of four nitrogen heterocycles proposed for anticancer therapy. Methods: Four 2-cyano-N-phenylacrylamine type derivatives containing acridine (3a), quinoline (3b), indole (3c), and pyridine (3d) nuclei were synthesized and characterized. They were evaluated for their ability to interact with DNA, physicochemical and pharmacokinetic predictions, in vitro and in silico methodologies, besides in vitro inhibition of the Topoisomerase IIα enzyme, antiproliferative activity in tumor and non-tumor cells, hemolytic activity with human erythrocytes, and in vivo toxicological studies with zebrafish embryos. Results: UV–vis absorption studies with ssDNA revealed different spectroscopic effects, with binding constants (Kb) ranging from 1.41 × 10⁵ to 6.46 × 10⁴ M⁻¹. The fluorescence quenching constant (Ksv) with ethidium bromide (EB) varied between 0.53 and 0.67 × 10³ M⁻¹. The compounds intercalated into DNA base pairs, a mechanism confirmed by molecular docking, with 3b (quinoline) showing the most substantial interaction. All derivatives exhibited antitopoisomerase IIα activity at 100 μM and were cytotoxic against MCF-7 and T47-D breast tumor cells, particularly against the more aggressive T47-D lineage. No hemolytic activity was observed in human erythrocytes. In vivo assays in zebrafish embryos showed no toxicological or cardiotoxic effects. However, all compounds altered superoxide dismutase (SOD) and catalase (CAT) enzymatic activity, requiring further studies on reactive oxygen species (ROS) generation to assess potential adverse effects. Furthermore, significant results were observed in the physicochemical and pharmacokinetic parameters of the synthesized compounds. Conclusions: The findings highlight the quinoline derivative (3b) as the most promising nitrogen heterocycle due to its antiproliferative activity and biomolecular interactions without adverse effects in zebrafish embryos, distinguishing it from clinically available agents. Full article

Per- and polyfluoroalkyl substances (PFAS), commonly known as “forever chemicals,” are a category of manufactured compounds that have been widely used in applications such as firefighting foams, clothing, cookware, cosmetics, and food packaging since the 1940s. These chemicals are known to bioaccumulate in many species, including humans, with half-lives numbering years and decades. Many of these chemicals are already known for their acute and chronic adverse effects on human health, and the list of confirmed harmful outcomes has continued to grow quickly. Since PFAS are persistent in the environment and everyday products, the cumulative exposure risk is quite high. Recently, PFAS have come under regulatory scrutiny, with safe exposure limit guidelines being consistently lowered as detection methods continue to improve. The majority of the research cataloging the effects of PFAS on human health have, thus far, been concentrated around the development of reliable detection methods and mitigation strategies. Only recently have efforts shifted towards investigations of how PFAS affect biomolecular function in membranes and proteins. To aid future research on PFAS interactions with biomolecules, this review summarizes the current state of knowledge about PFAS impact on the structure and function of albumins, hemoproteins, nuclear receptors, and membrane receptors. Full article

Microbial imbalance and the spread of pathogenic microorganisms pose severe threats to human health and ecological security. Traditional microbial detection methods suffer from several drawbacks such as long detection time, low sensitivity, and insufficient specificity. As an emerging fluorescent probe, carbon dots (CDs) offer an innovative direction for microbial labeling and detection due to their ultra-small particle size, unique optical properties, excellent biocompatibility, and facile surface modifiability. Herein, this article reviews the research progress of CDs on microbial labeling and detection. The content covers a brief introduction of CDs and explores the main recognition strategies including non-covalent interactions and biomolecule-mediated targeted binding. It also elaborates on the application status of multi-modal sensing technologies for microbial detection, such as CDs-based fluorescent sensing, electrochemical sensing, and surface-enhanced Raman scattering (SERS) sensing. Additionally, the challenges faced in current research, such as achieving simultaneous detection of multiple pathogens and in vivo dynamic tracking, are analyzed, and the development prospects of CDs in fields like clinical diagnosis and public health monitoring are prospected. This review aims to provide comprehensive references for further research and application of CDs in the field of microbial detection. Full article

The complexes cis-[Ru(dmbpy)₂Cl(bpy)](PF₆) (Rubpy) and cis-[Ru(dmbpy)₂Cl(bpe)](PF₆) (Rubpe) (dmbpy = 4,4′-Dimethyl-2,2′-dipyridyl, bpy= 4,4′-dipyridyl and bpe = 1,2-bis(4-pyridyl)ethane) were synthesized and spectroelectrochemically characterized. Both Ru(II) complexes exhibited absorption bands assigned to intraligand and metal-to-ligand charge transfer (MLCT) transitions, and their spectral stability in PBS buffer (pH 7.4) supports their suitability for biological studies involving biomolecules or living cells. Fluorescence quenching assays revealed strong interactions with bovine serum albumin (BSA), with binding constants (K_b) values were 2.89 × 10⁵ M⁻¹ for Rubpy and 1.97 × 10⁵ M⁻¹ for Rubpe, and a stoichiometry of one binding site per albumin molecule. DNA-binding studies demonstrated non-covalent interactions with ss-DNA, evidenced by a hyperchromic effect in the MLCT bands, suggesting a partial intercalation or groove-binding mechanism. Cellular uptake assays indicated moderate incorporation of both complexes in tumor cells, with uptake levels of 52% (Rubpy) and 47% (Rubpe) in HeLa cells, and 42% (Rubpy) and 32% (Rubpe) in MDA-MB-231 cells. Despite the similar uptake profiles, cytotoxicity assays showed that Rubpe is approximately 2.4 times more potent than Rubpy, with IC₅₀ values of 9 μM (HeLa) and 12 μM (MDA-MB-231), compared to 22 μM and 29 μM for Rubpy, respectively. These results highlight the relevance of these Ru(II) complexes as molecular platforms for exploring structure–activity relationships in anticancer agents. Full article

Understanding interactions between cations and DNA is essential for elucidating the structural dynamics of this fundamental biomolecule. While B-DNA is well known to dominate in long genomic DNA under physiological ionic conditions, its stability in very short DNA fragments—particularly in dilute solutions and in crude oligonucleotide preparations—has remained largely unexplored. Previous spectroscopic studies have primarily focused on long DNA, highly purified oligonucleotides, or high-salt environments, where collective polyion effects dominate. In contrast, the present results demonstrate that even in the absence of chain overlap and under low-salt conditions, Mg²⁺ ions efficiently stabilize the B-form by screening phosphate–phosphate electrostatic repulsion at the intrachain level. The ability to induce an A-to-B transition in crude, ultra-short DNA fragments highlights the fundamental role of divalent counterions in governing DNA conformation and establishes a lower bound for the length scale at which B-DNA can be stabilized. These findings are particularly relevant for dilute biological systems, fragmented DNA samples, and analytical protocols where short DNA fragments and low ionic strength are unavoidable. Full article

The growing recognition of probiotics’ beneficial effects on human health has significantly increased the need to identify, quantify, and characterize these microorganisms. In this context, Fourier-transform infrared (FTIR) and Raman spectroscopies have become indispensable analytical tools in probiotic research, offering non-invasive, rapid, and precise insights into the molecular structure and composition of probiotic strains. Likewise, these spectroscopic methods have also been shown relevant to investigate other bacterial species beyond probiotics. This review explores the principles of FTIR and Raman spectroscopies, emphasizing their role in identifying key biomolecules within bacterial cells, with particular focus on probiotics. Key applications of these vibrational spectroscopies in bacterial research include analyzing cell composition, evaluating encapsulation techniques, and monitoring responses to environmental stress, all of which contribute to enhanced stability and efficacy of probiotic formulations. Furthermore, FTIR and Raman spectroscopies assist in strain identification, investigation of bacteria-water interactions, and quality control, thereby supporting improved formulation and quality assurance. Collectively, these techniques demonstrate significant potential to drive innovation in the probiotics industry through precise strain customization, improved product stability, and robust quality control processes. Full article

Lanthanide ions and their complexes have emerged as versatile tools in biology and medicine owing to their unique photophysical, magnetic, and coordination properties. Their applications span bioimaging, sensing, therapy and diagnostics, underpinned by their strong preference for oxygen-donor ligands, kinetic stability, and tunable luminescence. This review integrates current developments in lanthanide coordination chemistry, focusing on the mechanistic basis of their interactions with biomolecules such as nucleic acids, proteins, and peptides. Moreover, this work highlights the design principles governing complex stability and biological compatibility, summarizing key biomedical uses of lanthanides ranging from imaging and drug delivery to anticancer and antioxidant effects, and discusses their toxicity and biodistribution, and their potential for clinical translation. In particular, this review offers a mechanistically oriented synthesis of recent advances, emphasizing the interplay between coordination behavior and biological function, and identifying emerging trends that define the current landscape of lanthanide-based bioinorganic research. By correlating molecular coordination features with biological performance, the review identifies the main trends shaping lanthanide-based bioinorganic research, also including a brief discussion of complexes formed between lanthanides and naturally occurring molecules, such as amino acids. Full article

Polymers and their composites have introduced significant advancements in engineering and technology. The primary advantages of polymeric materials include their lightweight nature, ease of manufacturing, anti-corrosion properties, reduced power consumption during assembly and integration, as well as enhanced stiffness, durability, and fatigue resistance. Polymer coatings with conductive polymers allow efficient charge transfer and make electrodes more flexible, helping them better match the mechanical properties of soft tissues. In addition, polymer coatings can protect electrodes from corrosion, reduce biofouling, and provide sites for attaching biomolecules, making them essential for reliable and long-term bioelectrode and biosensor performance. Polymer coatings for electrochemical bioelectrodes play a crucial role in enhancing sensor performance and stability in biological environments as they improve the interaction between electronic devices and biological tissues. These coatings enhance biocompatibility by reducing inflammation and tissue damage while also lowering electrode impedance to improve signal quality. The present review focuses on the most recent developments in polymer coatings for electrochemical biosensors and respective applications. The manuscript provides an overview of polymer materials, emerging strategies, coating approaches, and the resulting enhancements in bioelectrochemical applications. Full article

Nanotechnology is becoming a key tool in plant biotechnology, enabling nanoparticles (NPs) to deliver biomolecules with high precision and to enhance plant and tissue resilience under stress. However, the literature remains fragmented across genetic delivery, in vitro regeneration, stress mitigation, and germplasm cryopreservation, and it still lacks standardized, comparable protocols and robust long-term safety assessments—particularly for NP use in cryogenic workflows. This review critically integrates recent advances in NP-enabled (i) genetic engineering and transformation, (ii) tissue culture and regeneration, (iii) nanofertilization and abiotic stress mitigation, and (iv) cryopreservation of plant germplasm. Across these areas, the most consistent findings indicate that NPs can facilitate targeted transport of DNA, RNA, proteins, and regulatory complexes; modulate oxidative and osmotic stress responses; and improve regeneration performance in recalcitrant species. In cryopreservation, selected nanomaterials act as multifunctional cryoprotective adjuvants by suppressing oxidative injury, stabilizing cellular membranes, and improving post-thaw viability and regrowth of sensitive tissues. At the same time, NP outcomes are highly context-dependent, with efficacy governed by dose, size, and surface chemistry; formulation; plant genotype; and interactions with culture media or vitrification solutions. Evidence of potential phytotoxicity, persistence, and biosafety risks highlights the need for harmonized reporting, mechanistic studies on NP–cell interfaces, and evaluation of environmental fate. Expected outcomes of this review include a consolidated framework linking NP properties to biological endpoints, identification of design principles for application-specific NP selection, and a set of research priorities to accelerate the safe and reproducible translation of nanotechnology into sustainable plant biotechnology and long-term germplasm preservation. Full article

Titanium (Ti) and its alloys are widely used in biomedical applications due to their biocompatibility and corrosion resistance; however, surface modifications are required to enhance biological functionality. Surface functionalization using natural biomolecules has emerged as a promising strategy to improve early cell–surface interactions and biocompatibility of implant materials. In this study, Ti6Al4V alloy surfaces were biofunctionalized using Spirulina platensis (S. platensis) biomass and protein extract to evaluate morphological, chemical, and biological effects. The functionalization process involved activation with piranha solution, silanization with 3-aminopropyltriethoxysilane (APTES), and subsequent biomolecule immobilization. Surface characterization by scanning electron microscopy (SEM), inductively coupled plasma mass spectrometry (ICP-MS), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR) confirmed the successful incorporation of microalgal components, including nitrogen-, phosphorus-, and oxygen-rich organic groups. Biomass-functionalized surfaces exhibited higher phosphorus and oxygen content, while protein-coated surfaces showed nitrogen-enrich chemical signatures, reflecting the distinct molecular compositions of the immobilized biomolecules. Cell adhesion assays demonstrated enhanced early cell attachment on biofunctionalized surfaces, particularly in samples functionalized with 5 g/L biomass for three hours, which showed significantly greater cell attachment than both the control and protein-treated samples. These findings highlight the complementary yet distinct roles of S. platensis biomass and protein extract in modulating surface chemistry and cell–material interactions, emphasizing the importance of tailoring biofunctionalization strategies to optimize early biological responses on titanium-based implants. Full article

The detection of chiral properties is crucial for pharmacology and biochemistry, yet standard circular dichroism spectroscopy suffers from low sensitivity when probing minute sample volumes. While complex asymmetric chiral nanostructures can enhance these Circular Dichroic (CD) signals, their fabrication is intricate and costly. In this work, we analyzed an alternative based on extrinsic chirality in achiral square arrays of plasmonic circular NHAs realized via Displacement Talbot Lithography (DTL), thus exploring the chiroptical response arising from symmetry breaking induced by oblique illumination. Unlike isolated nanoparticles, nanohole arrays (NHAs) support propagating Surface Plasmon Polaritons (SPPs), allowing for unique light confinement capabilities essential for high-throughput sensing. A careful characterization in terms of Stokes parameters has been performed over a selected range of different optical angles of incidence and sample orientation to disentangle extrinsic chiral contribution from spurious effects related to sample imperfections. By optimizing such extrinsic chiral contributions, enhanced chiroptical response could be engineered by significantly amplifying the interaction between light and chiral biomolecules trapped within the holes. This methodology establishes DTL-fabricated achiral NHAs as an ultrasensitive, cost-effective platform for the detection and discrimination of enantiomers in biosensing applications. Full article

Background: Oral insulin improves compliance and convenience in patients with diabetes who require regular needle injections. However, the clinical application of oral insulin preparations has been limited due to instability and inefficient permeation through the gastrointestinal tract. In this study, a novel cationic polysaccharide nanodrug delivery platform was designed for efficient oral insulin delivery. Methods: The innovative thiolated trimethyl chitosan-grafted β-cyclodextrin (NCT) was synthesized by utilizing N-trimethyl chitosan (TMC) as the polymer backbone. This involved modifying TMC with thiol group-containing N-acetylcysteine and carboxymethyl-β-cyclodextrin that possesses hydrophobic cavities via an amide condensation reaction. Subsequently, this polymer was employed to construct the NCT nanoparticle system using an ionic cross-linking method. The physicochemical properties of the NCT nanoparticles were systematically analyzed, and their therapeutic efficacy was comprehensively evaluated in streptozotocin (STZ)-induced animal models. Results: The NCT nanoparticles demonstrated mucus adhesion, permeability, and pH sensitivity, which facilitated a slow and controlled release within the gastrointestinal microenvironment due to both ionic electrostatic interactions and disulfide bonding interactions. The experiments revealed in vivo that insulin/NCT nanoparticles extended the retention time of insulin in the small intestine. Blood glucose levels decreased to approximately 39% of the initial level at 5 h post-administration while exhibiting smooth hypoglycemic efficacy. Simultaneously, insulin bioavailability increased to 12.58%. Conclusions: The NCT nanoparticles effectively protect insulin from degradation in the gastrointestinal microenvironment while overcoming intestinal barriers, thereby providing a promising approach to oral biomolecule delivery. Full article