Electrochemical biosensor with aptamer/porous platinum nanoparticle on round-type micro-gap electrode for saxitoxin detection in fresh water

A probe-mediated fluorescent biosensor for MC-LR detection using exonuclease III as a signal amplifier

Microcystin-lr (MC-LR) is one of the most toxic and ubiquitous microcystins (MCs) released by cyanobacteria. Exposure to MC-LR can cause multiple organ damage and even death of the organism. Therefore, creating highly sensitive and dependable methods for detecting trace MC-LR is crucial. Herein, we developed a novel fluorescence aptasensor aided by exonuclease III (Exo III) for the highly sensitive detection of MC-LR. In the presence of MC-LR, the affinity interaction between MC-LR and aptamer A was triggered, leading to the release of blocker B. This unbound blocker can initiate Exo III-mediated signal amplification to digest the probe H, thereby recovering the fluorescence signal for readout. The proposed Exo III-assisted sensing platform demonstrated remarkable sensitivity and selectivity, achieving a limit of detection (LOD) of 0.37 ng L-1. Furthermore, it is robust and has been effectively utilized on water samples, achieving acceptable recovery rates (95.04-107.01%). With excellent sensitivity, high selectivity, efficient signal amplification, and fluorescence readout, the proposed biosensor offered a new and reliable alternative for the detection of trace MC-LR in the environment and the early warning of algal toxins.

Electroactive RuPt NPs programmed dual-channel electrochemical sensor for methyl mercaptan monitoring

The accurate and sensitive detection of methyl mercaptan (CH3SH) was of great significance for food corruption monitoring. Electroactive labels engineered electrochemical sensors possessed tailorable electrochemical responses, and showed potential prospects for CH3SH monitoring. In comparison to a single electrochemical signal, electroactive nanocomposites with multiple electrochemical responses not only provided multi-channel sensing signals for accurate detection, but also increased the peak intensity for sensitive detection. Herein, RuPt NPs were designed and explored to possess two independent and non-interfering electrochemical oxidation peaks at 0.75 V and -0.73 V. The formation of metal-SH covalent bonds between electroactive sites of RuPt NPs and CH3SH induced the changes of two electrochemical oxidation peaks. By utilizing the sum intensity of two electrochemical peaks as detection signal, a dual-channel electrochemical sensor was established for CH3SH detection in the range of 1 μM-1 mM, and had a low limit of detection (LOD) of 300 nM. This work gave a new insight into promoting more electroactive nanocomposites with multiple signals for accurate and sensitive electrochemical detection applications.

Sensing the Future-Frontiers in Biosensors: Exploring Classifications, Principles, and Recent Advances

Biosensors are transforming healthcare by delivering swift, precise, and economical diagnostic solutions. These analytical instruments combine biological indicators with physical transducers to identify and quantify biomarkers, thereby improving illness detection, management, and patient surveillance. Biosensors are widely utilized in healthcare for the diagnosis of chronic and infectious diseases, tailored treatment, and real-time health monitoring. This thorough overview examines several categories of biosensors and their uses in the detection of numerous biomarkers, including glucose, proteins, nucleic acids, and infections. Biosensors are commonly classified based on the type of transducer employed or the specific biorecognition element utilized. This review introduces a novel classification based on substrate morphology, offering a comprehensive perspective on biosensor categorization. Considerable emphasis is placed on the advancement of point-of-care biosensors, facilitating decentralized diagnostics and alleviating the strain on centralized healthcare systems. Recent advancements in nanotechnology have significantly improved the sensitivity, selectivity, and downsizing of biosensors, rendering them more efficient and accessible. The study examines problems such as stability, reproducibility, and regulatory approval that must be addressed to enable the widespread implementation of biosensors in clinical environments. The study examines the amalgamation of biosensors with wearable devices and smartphones, emphasizing the prospects for ongoing health surveillance and individualized medical care. This viewpoint clarifies the distinct types of biosensors and their particular roles, together with recent developments in the "smart biosensor" sector, facilitated by artificial intelligence and the Internet of Medical Things (IoMT). This novel approach seeks to deliver a comprehensive evaluation of the present condition of biosensor technology in healthcare, recent developments, and prospective paths, emphasizing their significance in influencing the future of medical diagnostics and patient care.

Competitive electrochemical aptasensor for high sensitivity detection of liver cancer marker GP73 based on rGO-Fc-PANi nanocomposites

Golgi protein 73 (GP73) is a novel tumor marker in the early diagnosis and prognosis of hepatocellular carcinoma (HCC). Herein, a competitive electrochemical aptasensor for detecting GP73 was constructed using reduced graphene oxide-ferrocene-polyaniline nanocomposite (rGO-Fc-PANi) as the biosensing platform. The rGO-Fc-PANi had larger specific surface area, excellent conductivity and outstanding electroactive performance, which served as nanocarrier for GP73 aptamer (GP73Apt) binding and as redox nanoprobe for record electrical signal. Then, a complementary chain (cDNA) was fixed to the electrode by hybridization with GP73Apt. When GP73 was present, a competitive process happened among cDNA, GP73Apt and GP73, formed the GP73-GP73Apt stable chemical structure and made cDNA detach from the sensing electrode, resulting in enhancement of electrical signal. The difference in the corresponding peak current before and after the competition can be used to indicate the quantitative of GP73. Under optimal conditions, the DPV current response showed a good log-linear relationship with GP73 concentrations (0.001 ∼ 100.0 ng/mL) with a detection limit of 0.15 pg/mL (S/N = 3). It was successfully used for GP73 detection in human serum with RSDs ranging from 1.08 % to 6.96 %. Therefore, the aptasensor could provide an innovative technology platform and hold a great potential in clinical application.

A rapid field-ready electrical biosensor consisting of bismuthine-derived Au island decorated BiOCl nanosheets for Raphidiopsis raciborskii detection in freshwater

Cyanobacteria play an essential role in nutrient cycling in aquatic ecosystems. However, certain species adversely affect the environment and human health by causing harmful cyanobacterial algal blooms (cyanoHABs) and producing cyanotoxins. To address this issue, continuous cyanoHAB monitoring has been considered; however, a gold standard has not yet been established. In this study, we aimed to develop a dual DNA-targeting capacitive-type biosensor for rapid field-ready monitoring of Raphidiopsis raciborskii, a causative species of cyanoHAB. To enhance the sensing signal, a plate-like Au-BiOCl nanocomposite was synthesized using a spontaneous carbonation process without additional additives. The alternating-current electrothermal flow (ACEF) technique was applied to enable rapid DNA and probe binding within 10 min. The limits of detection (LODs) for R. raciborskii RubisCO large subunit (rbcL) and RNA polymerase beta subunit (rpoB) genes diluted in deionized (DI) water were 4.89 × 10-17 and 3.89 × 10-17 M, respectively. Furthermore, the LODs of R. raciborskii rbcl and rpoB diluted in freshwater containing HAB were 2.55 × 10-16 and 3.84 × 10-16 M, respectively, demonstrating the field-ready applicability of the device. The fabricated cyanobacterial DNA-sensing platform enabled powerful species-specific detection using a small sample volume and low target concentration without a nucleic acid amplification step, dramatically reducing the detection time. This study has considerable implications for detecting HABs, early warning systems, and species-specific environmental monitoring technology.

Highly sensitive and selective electrochemical biosensor using odorant-binding protein to detect aldehydes

Recently, various biosensors based on odorant-binding proteins (OBPs) were developed for the detection of odorants and pheromones. However, important data gaps exist regarding the sensitive and selective detection of aldehydes with various carbon numbers. In this work, an OBP2a-based electrochemical impedance spectroscopy (EIS) biosensor was developed by immobilizing OBP2a on a gold interdigital electrode, and was characterized by EIS and atomic force microscopy. EIS responses showed the OBP2a-based biosensor was highly sensitive to citronellal, lily aldehyde, octanal, and decanal (detection limit of 10-11 mol/L), and was selective towards aldehydes compared with interfering odorants such as small-molecule alcohols and fatty acids (selectivity coefficients lower than 0.15). Moreover, the OBP2a-based biosensor exhibited high repeatability (relative standard deviation: 1.6%-9.1 %, n = 3 for each odorant), stability (NIC declined by 3.6 % on 6th day), and recovery (91.2%-96.6 % on three real samples). More specifically, the sensitivity of the biosensor to aldehydes was positively correlated to the molecular weight and the heterocyclic molecule structure of the odorants. These results proved the availability and the potential usage of the OBP2a-based EIS biosensor for the rapid and sensitive detection of aldehydes in aspects such as medical diagnostics, food and favor analysis, and environmental monitoring.

Nanopillar array-based electrochemical aptamer sensor for STX sensitivity detection

Saxitoxin (STX) is a cyanotoxin with high toxicity, and therefore, there is an urgent need to develop a facile detection method for STX. In this study, an ordered nanopillar array-based electrochemical aptasensor was fabricated for the high-performance detection of STX. The anti-STX aptamer with methylene blue (MB) incorporated at the 3'-end (MB-Apt) was immobilized at the surface of an Au@PAN nanopillar array electrode and used as the recognition element. The proposed aptasensor demonstrated highly sensitive and selective STX detection because of synergistic catalysis effects of MB and ordered nanopillar arrays along with the selection of MB-Apt. The nanopillar array-based electrochemical aptasensor exhibited high sensitivity over a wide linear concentration range of 1 pM-3 nM with a linear regression equation of ΔI (μA) = 28.0 + 6.9 × log[STX] (R2 = 0.98079) and 3-100 nM with a linear regression equation of ΔI (μA) = 10.7 + 43.4 × log[STX] (R2 = 0.98772), where R is the correlation coefficient. In addition, the limit of detection (LOD) was as low as 1 pM. Furthermore, the designed aptasensor demonstrated excellent selectivity toward STX, preventing interference from neo-STX, okadaic acid, and common metal ions. The presented orderly nanopillar array-based strategy to develop an electrochemical aptasensor for STX detection offers a promising method for developing high-performance electrochemical sensors, and the presented aptasensor should find useful application in the detection of shellfish poison.

Advances in Biosensors for the Rapid Detection of Marine Biotoxins: Current Status and Future Perspectives

Marine biotoxins (MBs), harmful metabolites of marine organisms, pose a significant threat to marine ecosystems and human health due to their diverse composition and widespread occurrence. Consequently, rapid and efficient detection technology is crucial for maintaining marine ecosystem and human health. In recent years, rapid detection technology has garnered considerable attention for its pivotal role in identifying MBs, with advancements in sensitivity, specificity, and accuracy. These technologies offer attributes such as speed, high throughput, and automation, thereby meeting detection requirements across various scenarios. This review provides an overview of the classification and risks associated with MBs. It briefly outlines the current research status of marine biotoxin biosensors and introduces the fundamental principles, advantages, and limitations of optical, electrochemical, and piezoelectric biosensors. Additionally, the review explores the current applications in the detection of MBs and presents forward-looking perspectives on their development, which aims to be a comprehensive resource for the design and implementation of tailored biosensors for effective MB detection.

Electrochemical peptide-based biosensor for the detection of the inflammatory disease biomarker, interleukin-1beta

This paper reports the development of a highly sensitive and selective electrochemical peptide-based biosensor for the detection of the inflammatory disease biomarker, interleukin-1beta (IL-1β). To this end, flower-like Au-Ag@MoS2-rGO nanocomposites were used as the signal amplification platform to achieve a label-free biosensor with a high sensitivity and selectivity. First, a high-affinity peptide for IL-1β was identified through biopanning with M13 random peptide libraries, and was newly designed by incorporating cysteine at the C-terminus. An IL-1β specific binding peptide was used as the bio-receptor, and the interaction between the IL-1β binding peptide and IL-1β was confirmed via enzyme-linked immunosorbent assay and various physicochemical and electrochemical analyses. Under optimal conditions, the biosensor achieved an ultrasensitive and specific IL-1β detection in a wide linear concentration range of 0-250 ng/mL with a picomolar-level detection limit (∼2.4 pM), low binding constant (∼0.62 pM), and a low coefficient of variation (<1.65 %). The biosensor was successfully utilized for IL-1β determination in the serum of Crohn's disease patients with a good correlation coefficient. In addition, the detection performance was comparable to that of commercially available IL-1β ELISA kit. This indicates that the electrochemical peptide-based biosensor may offer a potentially valuable platform for the clinical diagnosis of various inflammatory disease biomarkers.

Development of a highly sensitive aptamer-based electrochemical sensor for detecting saxitoxin based on K3Fe(CN)6 regulated silver nanoparticles

BACKGROUND

Saxitoxin (STX) is the most toxic marine toxin, which can pose several adverse effects on human health. High sensitivity, fast response, and low-cost detection of STX contamination are of significance to reducing the fishery and seafood industries' loss. Among the various types of biosensors, the electrochemical biosensors have been extensively studied in the detection of STX, but the electrode surface modification material is easy to fall off, resulting in unstable electrochemical signals and poor reproducibility. It is imperative to have a ratiometric electrochemical biosensor for STX.

RESULTS

In this study, we developed a novel aptamer-based electrochemical sensor (AECs) for the sensitive detection of STX based on a K3Fe(CN)6 regulated silver nanoparticles (Ag NPs) modified with aptamer. The AECs was constructed by immobilizing aptamer on Ag NPs surfaces. Under optimized conditions, the AECs showed a linear response towards STX in the range from 0.04 to 0.15 μM with the regression equation of Y = -8.0 + 233.7 X (R2 = 0.9956). The limit of detection (LOD) was calculated to be 1 nM (based on 3 N/S), which is significantly lower than the regulatory limits for STX in seafood. Moreover, the AECs showed excellent sensitivity, reproducibility and stability, as well as the detection in samples with acceptable recovery ranged from 71.2 % to 93.8 %, demonstrating its broad application prospects in detection of STX in seafood samples.

SIGNIFICANCE

This work proposed an AECs to achieve sensitive detection of STX. A reaction system of K3Fe(CN)6 etched Ag NPs was introduced and used as the signal source to avoid the instability of the electrochemical signal, which can produce a ratiometric electrochemical signal output mode, improving the stability and sensitivity of electrochemical detection of STX.

Recent Advances in Metallic Nanostructures-assisted Biosensors for Medical Diagnosis and Therapy

The field of nanotechnology has witnessed remarkable progress in recent years, particularly in its application to medical diagnosis and therapy. Metallic nanostructures-assisted biosensors have emerged as a powerful and versatile platform, offering unprecedented opportunities for sensitive, specific, and minimally invasive diagnostic techniques, as well as innovative therapeutic interventions. These biosensors exploit the molecular interactions occurring between biomolecules, such as antibodies, enzymes, aptamers, or nucleic acids, and metallic surfaces to induce observable alterations in multiple physical attributes, encompassing electrical, optical, colorimetric, and electrochemical signals. These interactions yield measurable data concerning the existence and concentration of particular biomolecules. The inherent characteristics of metal nanostructures, such as conductivity, plasmon resonance, and catalytic activity, serve to amplify both sensitivity and specificity in these biosensors. This review provides an in-depth exploration of the latest advancements in metallic nanostructures-assisted biosensors, highlighting their transformative impact on medical science and envisioning their potential in shaping the future of personalized healthcare.

Fast-response electrochemical biosensor based on a truncated aptamer and MXene heterolayer for West Nile virus detection in human serum

West Nile virus (WNV) is a mosquito-borne flavivirus that can cause West Nile fever, meningitis, encephalitis, and polio. Early detection of WNV is important to prevent infection spread on the field. To commercialize the electrochemical biosensor for WNV, rapid target detection with the cheap manufacture cost is essential. Here, we developed a fast-response electrochemical biosensor consisting of a truncated WNV aptamer/MXene (Ti3C2Tx) bilayer on round-type micro gap. To reduce the target binding time, the application of the alternating current electrothermal flow (ACEF) technology reduced the target detection time to within 10 min, providing a rapid biosensor platform. The MXene nanosheet improved electrochemical signal amplification, and the aptamer produced through systematic evolution of ligands by exponential enrichment process eliminated unnecessary base sequences via truncation and lowered the manufacturing cost. Under optimized conditions, the WNV limit of detection (LOD) and selectivity were measured using electrochemical measurement methods, including cyclic voltammetry and square wave voltammetry. The LOD was 2.57 pM for WNV diluted in deionized water and 1.06 pM for WNV diluted in 10% human serum. The fabricated electrochemical biosensor has high selectivity and allows rapid detection, suggesting the possibility of future application in the diagnosis of flaviviridae virus.

Highly sensitive electrochemical peptide-based biosensor for marine biotoxin detection using a bimetallic platinum and ruthenium nanoparticle-tethered metal-organic framework modified electrode

Saxitoxin (STX) is a highly toxic small-molecule cyanotoxin that is water-soluble, stable in acidic media, and thermostable. STX is hazardous to human health and the environment in ocean, thus it is an important to detect it at very low concentrations. Herein, we developed an electrochemical peptide-based biosensor for the trace detection of STX in different sample matrix utilizing differential pulse voltammetry (DPV) signal. We synthesized the nanocomposite of zeolitic imidazolate framework-67 (ZIF-67) decorated bimetallic platinum (Pt) and ruthenium (Ru) nanoparticles (Pt-Ru@C/ZIF-67) using impregnation method. The nanocomposite modified with screen-printed electrode (SPE) was subsequently used to detect STX in the range of 1-1,000 ng mL^-1, with a detection limit (LOD) of 26.7 pg mL^-1. The developed peptide-based biosensor is highly selective and sensitive towards STX detection, thus it represents a promising strategy for the development of novel portable bioassay for monitoring various hazardous molecules in aquatic food chains.

Construction of a rapid electrochemical biosensor consisting of a nanozyme/aptamer conjugate for waterborne microcystin detection

Microcystin-LR (MC-LR) is a hepatotoxin generated by the excessive proliferation of cyanobacteria, which is a threat to humans and wildlife. Therefore, rapid detection of MC-LR is an important challenge. This study describes a rapid electrochemical biosensor comprising nanozymes and aptamers. Alternating current electrothermal flow (ACEF) significantly reduced the MC-LR detection period to 10 min. We also used MnO₂/MC-LR aptamer conjugates to improve the sensitivity to MC-LR detection. Here, MnO₂ amplified the electrochemical signal and the aptamer showed high selectivity for MC-LR. Under the optimal conditions, the limit of detection (LOD) and selectivity in freshwater were detected using cyclic voltammetry and differential pulse voltammetry. As a result, an LOD of 3.36 pg mL^-1 was observed in the linear concentration range of 10 pg mL^-1 to 1 μg mL^-1. This study quickly and sensitively detected MC-LR in a situation where it causes serious damage worldwide. In addition, the ACEF technology introduction is the first example of MC-LR detection, suggesting a wide range of possibilities for MC-LR biosensors.

Detection of saxitoxin by a SERS aptamer sensor based on enzyme cycle amplification technology

Saxitoxin (STX) is a typical toxic guanidinium neurotoxin, one of the paralytic shellfish poisons (PSP), which poses a serious threat to human health. In this paper, a simple and sensitive SERS aptamer sensor (abbreviated as AuNP@4-NTP@SiO₂) for the quantitative determination of STX was developed. Hairpin aptamers of saxitoxin are modified on magnetic beads and used as recognition elements. In the presence of STX, DNA ligase, and the rolling circle template (T1), a rolling circle amplification reaction was triggered to produce long single-stranded DNA containing repetitive sequences. The sequence can be hybridized with the SERS probe to realize the rapid detection of STX. Due to the inherent merits of its components, the obtained AuNP@4-NTP@SiO₂ SERS aptamer sensor manifests excellent sensing performance for STX detection with a wide linear range from 2.0 × 10^-10 mol L^-1 to 5.0 × 10^-4 mol L^-1 and a lower detection limit of 1.2 × 10^-11 mol L^-1. This SERS sensor can provide a strategy for the micro-detection of other biological toxins by changing the aptamer sequence.

Rapid electrochemical biosensor composed of DNA probe/iridium nanoparticle bilayer for Aphanizomenon flos-aquae detection in fresh water

Toxic cyanobacteria pose a serious threat to aquatic ecosystems and require adequate detection and control systems. Aphanizomenon flos-aquae is a harmful cyanobacterium that produces the toxicant saxitoxin. Therefore, it is necessary to detect the presence of A. flos-aquae in lakes and rivers. We proposed a rapid electrochemical biosensor composed of DNA primer/iridium nanoparticles (IrNP) bilyer for the detection of A. flos-aquae in freshwater. The extracted A. flos-aquae gene (rbcL-rbcX) is used as a target, and it was fixed to the electrode using a 5'-thiolated DNA primer (capture probe). Then, Avidin@IrNPs complex for amplification of electrical signals was bound to the target through a 3'-biotinylated DNA primer (detection probe). To rapidly detect the target, an alternating current electrothermal flow technique was introduced in the detection step, which could reduce the detection time to within 20 min. To confirm the biosensor fabrication, atomic force microscopy was used to investigate the surface morphology. To evaluate the biosensor performance, cyclic voltammetry and electrochemical impedance spectroscopy were used. The target gene was detected at a concentration of 9.99 pg/mL in tap water, and the detection range was 0.1 ng/mL to 10³ ng/mL with high selectivity. Based on the combined system, we employed A. flos-aquae in tap water. This rapid cyanobacteria detection system is a powerful tool for CyanoHABs in the field.

Flexible Label-Free Platinum and Bio-PET-Based Immunosensor for the Detection of SARS-CoV-2

The demand for new devices that enable the detection of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) at a relatively low cost and that are fast and feasible to be used as point-of-care is required overtime on a large scale. In this sense, the use of sustainable materials, for example, the bio-based poly (ethylene terephthalate) (Bio-PET) can be an alternative to current standard diagnostics. In this work, we present a flexible disposable printed electrode based on a platinum thin film on Bio-PET as a substrate for the development of a sensor and immunosensor for the monitoring of COVID-19 biomarkers, by the detection of L-cysteine and the SARS-CoV-2 spike protein, respectively. The electrode was applied in conjunction with 3D printing technology to generate a portable and easy-to-analyze device with a low sample volume. For the L-cysteine determination, chronoamperometry was used, which achieved two linear dynamic ranges (LDR) of 3.98-39.0 μmol L-1 and 39.0-145 μmol L-1, and a limit of detection (LOD) of 0.70 μmol L-1. The detection of the SARS-CoV-2 spike protein was achieved by both square wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS) by a label-free immunosensor, using potassium ferro-ferricyanide solution as the electrochemical probe. An LDR of 0.70-7.0 and 1.0-30 pmol L-1, with an LOD of 0.70 and 1.0 pmol L-1 were obtained by SWV and EIS, respectively. As a proof of concept, the immunosensor was successfully applied for the detection of the SARS-CoV-2 spike protein in enriched synthetic saliva samples, which demonstrates the potential of using the proposed sensor as an alternative platform for the diagnosis of COVID-19 in the future.

Recent Developments in DNA-Nanotechnology-Powered Biosensors for Zika/Dengue Virus Molecular Diagnostics

Zika virus (ZIKV) and dengue virus (DENV) are highly contagious and lethal mosquito-borne viruses. Global warming is steadily increasing the probability of ZIKV and DENV infection, and accurate diagnosis is required to control viral infections worldwide. Recently, research on biosensors for the accurate diagnosis of ZIKV and DENV has been actively conducted. Moreover, biosensor research using DNA nanotechnology is also increasing, and has many advantages compared to the existing diagnostic methods, such as polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). As a bioreceptor, DNA can easily introduce a functional group at the 5' or 3' end, and can also be used as a folded structure, such as a DNA aptamer and DNAzyme. Instead of using ZIKV and DENV antibodies, a bioreceptor that specifically binds to viral proteins or nucleic acids has been fabricated and introduced using DNA nanotechnology. Technologies for detecting ZIKV and DENV can be broadly divided into electrochemical, electrical, and optical. In this review, advances in DNA-nanotechnology-based ZIKV and DENV detection biosensors are discussed.

Recent Advances in Aptasensing Strategies for Monitoring Phycotoxins: Promising for Food Safety

Phycotoxins or marine toxins cause massive harm to humans, livestock, and pets. Current strategies based on ordinary methods are long time-wise and require expert operators, and are not reliable for on-site and real-time use. Therefore, it is urgent to exploit new detection methods for marine toxins with high sensitivity and specificity, low detection limits, convenience, and high efficiency. Conversely, biosensors can distinguish poisons with less response time and higher selectivity than the common strategies. Aptamer-based biosensors (aptasensors) are potent for environmental monitoring, especially for on-site and real-time determination of marine toxins and freshwater microorganisms, and with a degree of superiority over other biosensors, making them worth considering. This article reviews the designed aptasensors based on the different strategies for detecting the various phycotoxins.

Recent Progress in Nanotechnology-Based Approaches for Food Monitoring

Throughout the food supply chain, including production, storage, and distribution, food can be contaminated by harmful chemicals and microorganisms, resulting in a severe threat to human health. In recent years, the rapid advancement and development of nanotechnology proposed revolutionary solutions to solve several problems in scientific and industrial areas, including food monitoring. Nanotechnology can be incorporated into chemical and biological sensors to improve analytical performance, such as response time, sensitivity, selectivity, reliability, and accuracy. Based on the characteristics of the contaminants and the detection methods, nanotechnology can be applied in different ways in order to improve conventional techniques. Nanomaterials such as nanoparticles, nanorods, nanosheets, nanocomposites, nanotubes, and nanowires provide various functions for the immobilization and labeling of contaminants in electrochemical and optical detection. This review summarizes the recent advances in nanotechnology for detecting chemical and biological contaminations in the food supply chain.

A simple electrochemical aptasensor for saxitoxin detection

The combination between the electrochemical sensor and selective specificity of MB modified aptamer(MB-Apt) yielded an electrochemical aptasensor with a high sensitivity and excellent specific recognition ability to STX.