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Recent advances of nanozyme-enhanced electrochemical biosensors for antibiotic detection in foods: Trends, opportunities, and challenges
(2025-12-01) Garehbaghi, Sanam; Gharibzahedi, Seyed Mohammad Taghi; Altintas, Zeynep
Nanozyme (NZ)-enhanced electrochemical (EC) biosensors have significantly advanced as a result of the growing need for quick, sensitive, and on-site detection of antibiotic residues in food. This study thoroughly reviews the latest developments in NZ-based EC biosensors for the detection of antibiotics in food matrices, including conventional EC, electrochemiluminescence (ECL), photoelectrochemical (PEC), and dual-mode colorimetric-electrochemical (CM-EC) platforms. NZ-based biosensors have emerged as viable substitutes for traditional chromatographic techniques (such as HPLC and LC-MS/MS), which are still the gold standard for sensitivity and multi-residue analysis owing to their high cost, labor-intensive procedures, and lack of portability. Because of their enzyme-mimicking catalytic activity, NZs improve signal amplification, allowing for molecularly imprinted polymer (MIP) or aptamer recognition for ultrasensitive detection with low limits of detection and high specificity. Dual-mode CM-EC devices combine visual simplicity with quantitative precision, while ECL and PEC sensors further increase sensitivity by integrating light-driven processes and catalytic precipitation. Despite their advantages, challenges such as matrix effects, synthesis scalability, and cross-reactivity hinder widespread adoption. Miniaturization, smartphone integration, and increased uses in food safety monitoring are potential future developments.
2D graphene-based advanced nanoarchitectonics for electrochemical biosensors: Applications in cancer biomarker detection
(ELSEVIER ADVANCED TECHNOLOGY, 2024-04-15) Mukherjee, Soumajit; Mukherjee, Atripan; Bytešníková, Zuzana; Ashrafi, Amirmansoor; Richtera, Lukáš; Adam, Vojtěch
Low-cost, rapid, and easy-to-use biosensors for various cancer biomarkers are of utmost importance in detecting cancer biomarkers for early-stage metastasis control and efficient diagnosis. The molecular complexity of cancer biomarkers is overwhelming, thus, the repeatability and reproducibility of measurements by biosensors are critical factors. Electrochemical biosensors are attractive alternatives in cancer diagnosis due to their low cost, simple operation, and promising analytical figures of merit. Recently graphene-derived nanostructures have been used extensively for the fabrication of electrochemical biosensors because of their unique physicochemical properties, including the high electrical conductivity, adsorption capacity, low cost and ease of mass production, presence of oxygen-containing functional groups that facilitate the bioreceptor immobilization, increased flexibility and mechanical strength, low cellular toxicity. Indeed, these properties make them advantageous compared to other alternatives. However, some drawbacks must be overcome to extend their use, such as poor and uncontrollable deposition on the substrate due to the low dispersity of some graphene materials and irreproducibility of the results because of the differences in various batches of the produced graphene materials. This review has documented the most recently developed strategies for electrochemical sensor fabrication. It differs in the categorization method compared to published works to draw greater attention to the wide opportunities of graphene nanomaterials for biological applications. Limitations and future scopes are discussed to advance the integration of novel technologies such as artificial intelligence, the internet of medical things, and triboelectric nanogenerators to eventually increase efficacy and efficiency.
Distance-based paper microfluidic devices for rapid visual quantification of heavy metals in herbal supplements and cosmetics
(Royal Society of Chemistry, 2024-11-11) Manmana, Yanawut; Macka, Miroslav; Nuchtavorn, Nantana
Distance-based detection (DbD) on paper-based microfluidic analytical devices (mu PADs) has emerged as a promising, cost-effective, simple, and instrumentation-free assay method. Broadening the applicability of a new way of immobilization of reagent for DbD on mu PADs (D mu PADs) is presented, employing an ion exchange (IE) interaction of an anionic metallochromic reagent, 2-(5-bromo-2-pyridylazo)-5-[N-n-propyl-N-(3-sulfopropyl)amino]phenol (5-Br-PAPS), on the anion-exchange filter paper. The IE D mu PADs demonstrate superiority over standard cellulose filter paper in terms of the degree of reagent immobilization, detection sensitivity, and clear detection endpoints due to the strong retention of 5-Br-PAPS. The study investigated various parameters influencing DbD, including 5-Br-PAPS concentrations (0.25-1 mM), buffer types (acetic acid-Tris, MES), buffer concentrations (20-500 mM), and auxiliary complexing agents (acetic, formic, and glycolic acids). Subsequently, the performance of 17 metals (Ag+, Cd2+, Co2+, Cr3+, Cu2+, Fe2+, Hg2+, La2+, Mn2+, Ni2+, Pb2+, Ti2+, Zn2+, Al3+, As3+, Fe3+, and V4+) was evaluated, with color formation observed for 12 metals. Additionally, the paper surface was examined using SEM and SEM-EDX to verify the suitability of certain areas in the detection channel for reagent immobilization and metal binding. This method demonstrates quantitation limits of metals in the low mu g mL-1 range, showing great potential for the rapid screening of toxic metals commonly found in herbal supplements and cosmetics regulated by the Food and Drug Administration (FDA). Thus, it holds promise for enhancing safety and regulatory compliance in product quality assessment. Furthermore, this method offers a cost-effective, environmentally sustainable, and user-friendly approach for the rapid visual quantification of heavy metals for in-field analysis, eliminating the need for complex instrumentation.
Exploring the Frontiers of Cell Temperature Measurement and Thermogenesis
(WILEY, 2024-10-28) Zhu, Hanliang; Xu, Haotian; Zhang, Yue; Brodský, Jan; Gablech, Imrich; Korabečná, Marie; Neužil, Pavel
The precise measurement of cell temperature and an in-depth understanding of thermogenic processes are critical in unraveling the complexities of cellular metabolism and its implications for health and disease. This review focuses on the mechanisms of local temperature generation within cells and the array of methods developed for accurate temperature assessment. The contact and noncontact techniques are introduced, including infrared thermography, fluorescence thermometry, and other innovative approaches to localized temperature measurement. The role of thermogenesis in cellular metabolism, highlighting the integral function of temperature regulation in cellular processes, environmental adaptation, and the implications of thermogenic dysregulation in diseases such as metabolic disorders and cancer are further discussed. The challenges and limitations in this field are critically analyzed while technological advancements and future directions are proposed to overcome these barriers. This review aims to provide a consolidated resource for current methodologies, stimulate discussion on the limitations and challenges, and inspire future innovations in the study of cellular thermodynamics.
The impact of single and combined amendment of elemental sulphur and graphene oxide on soil microbiome and nutrient transformation activities
(Elsevier Ltd, 2024-10-15) Hammerschmiedt, Tereza; Holátko, Jiří; Bytešníková, Zuzana; Škarpa, Petr; Richtera, Lukáš; Kintl, Antonín; Pekárková, Jana; Kučerík, Jiří; Jaskulska, Iwona; Radziemska, Maja; Valová, Radmila; Malíček, Ondřej; Brtnický, Martin
Background: Sulphur (S) deficiency has emerged in recent years in European soils due to the decreased occurrence of acid rains. Elemental sulphur (S0) is highly beneficial as a source of S in agriculture, but it must be oxidized to a plant-accessible form. Micro- or nano-formulated S0 may undergo accelerated transformation, as the oxidation rate of S0 indirectly depends on particle size. Graphene oxide (GO) is a 2D-carbon-based nanomaterial with benefits as soil amendment, which could modulate the processes of S0 oxidation. Micro-and nano-sized composites, comprised of S0 and GO, were tested as soil amendments in a pot experiment with unplanted soil to assess their effects on soil microbial biomass, activity, and transformation to sulphates. Fourteen different variants were tested, based on solely added GO, solely added micro- or nano-sized S0 (each in three different doses) and on a combination of all S0 doses with GO. Results: Compared to unamended soil, nano-S0 and nano-S0+GO increased soil pH(CaCl2). Micro-S0 (at a dose 4 g kg1) increased soil pH(CaCl2), whereas micro-S0+GO (at a dose 4 g kg1) decreased soil pH(CaCl2). The total bacterial and ammonium oxidizer microbial abundance decreased due to micro-S0 and nano-S0 amendment, with an indirect dependence on the amended dose. This trend was alleviated by the co-application of GO. Urease activity showed a distinct response to micro-S0+GO (decreased value) and nano-S0+GO amendment (increased value). Arylsulfatase was enhanced by micro-S0+GO, while sulphur reducing bacteria (dsr) increased proliferation due to high micro-S0 and nano-S0, and co-amendment of both with GO. In comparison to nano-S0, the amendment of micro-S0+GO more increased soluble sulphur content more significantly. Conclusions: Under the conditions of this soil experiment, graphene oxide exhibited a significant effect on the process of sulphur oxidation.

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