Highly sensitive molecular imprinted voltammetric sensor for resveratrol assay in wine via polyaniline/gold nanoparticles signal enhancement and polyacrylamide recognition

Monitoring of Specific Phytoestrogens by Dedicated Electrochemical Sensors: A Review

Phytoestrogens are non-steroidal estrogens produced from plants that can bind with the human body's estrogenic receptor site and be used as a substitute for maintaining hormonal balance. They are mainly classified as flavonoids, phenolic acids, lignans, stilbenes, and coumestans; some are resocyclic acids of lactones, which are mycotoxins and not natural phytoestrogen. Phytoestrogens have many beneficial medicinal properties, making them an important part of the daily diet. Electrochemical sensors are widely used analytical tools for analysing various pharmaceuticals, chemicals, pollutants and food items. Electrochemical sensors provide an extensive platform for highly sensitive and rapid analysis. Several reviews have been published on the importance of the biological and medicinal properties of phytoestrogens. However, this review provides an overview of recent work performed through electrochemical measurements with electrochemical sensors and biosensors for all the classes of phytoestrogens done so far since 2019.

Electrochemical Sensors and Biosensors for the Determination of Food Nutritional and Bioactive Compounds: Recent Advances

The significance of food nutrients and bioactive compounds in human health has driven the development of many methods for their determination in different matrices. Among these, electroanalysis has gained popularity due to its cost-effectiveness, rapidity, and, in many cases, portability and minimal sample treatment. This review highlights key advances in electrochemical sensors and biosensors from 2019 to the present. Given the variability and the challenges of managing food matrices, the focus is limited to methods that have been thoroughly assessed for their applicability to real samples. The technical characteristics and analytical performance of the proposed sensors are discussed, along with breakthrough features and future trends.

Bimetallic porous Mn/Co oxide nanosheets with efficient oxidase-mimicking activity for the sensitive colorimetric determination of resveratrol in different matrices

BACKGROUND

Resveratrol, a natural polyphenol compound used as an ingredient in dietary supplements, and pharmaceuticals, has gained significant attention due to its potential health benefits. However, the accurate and sensitive determination of resveratrol in complex matrices remains a challenge. In this study, we propose the utilization of bimetallic porous Mn/Co oxide nanosheets (MnCoO-NSs) as catalysts for the colorimetric determination of resveratrol.

RESULTS

The bimetallic porous MnCoO-NSs were prepared through a facile one-stone-two-birds strategy. These nanosheets exhibited superior oxidase-mimicking activity, as evidenced by the catalytic oxidation of the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB), producing a blue-colored oxTMB species with a prominent absorbance peak at 655 nm. The catalytic activity was promoted through the production of superoxide anion (O2•-), which enhanced the affinity of MnCoO-NSs to the TMB molecules. Upon the addition of resveratrol, the oxidation process was inhibited, resulting in rapid fading of the blue color. This colorimetric sensing platform exhibited a linear response to resveratrol concentrations over the range of 2.2-87.6 μM, with a limit of detection of 0.210 μM. The method was further applied for the determination of resveratrol in different matrices including biological fluids, pharmaceuticals, and environmental water.

SIGNIFICANCE

The utilization of these MnCoO-NSs offers a simple and cost-effective alternative to conventional analytical techniques for the determination of resveratrol. Their high sensitivity, selectivity, and stability enable accurate measurements of resveratrol in various complex matrices. This research has implications in areas such as pharmaceutical analysis, biomedical research, and environmental analysis, where the reliable determination of resveratrol is crucial for assessing its therapeutic potential and ensuring product quality.

A novel copper-based nanozyme: fabrication and application for colorimetric detection of resveratrol

A novel nanozyme (urea@Cu-NF) was synthesized by self-assembly of urea and copper phosphate with urea as plasticizer. Urea@Cu-NF exhibited excellent peroxidase-like activity with the ability to oxidize TMB in the presence of H2O2. However, its peroxidase-like activity could be inhibited by resveratrol, leading to an absorption decrease in the intensity of oxTMB. Based on this phenomenon, a colorimetric method was designed for resveratrol detection. The colorimetric reaction could be completed within 20 min with a linear range of 1-120 μM. The limit of detection (LOD) of resveratrol is 0.43 μM. Our experimental results demonstrate that urea@Cu-NF has enormous potential to function as a cheap and accurate quality detection tool.

Molecular imprinted electrochemical sensor for ovalbumin detection based on boronate affinity and signal amplification approach

Ovalbumin (OVA), a class of glycoproteins, is the main allergen in hen egg white that often causes allergies in humans, especially in babies. Therefore, it is pivotal to be able to detect and separate OVA. This work presents an ingenious sandwich-structured magnetic molecular imprinted electrochemical sensor for OVA detection by utilizing boronate affinity and signal amplification strategy. With anti-OVA antibody-modified gold nanoparticles (AuNPs) as amplifiers, the imprinted cavities in the probe could capture protein to form a sandwich structure. Due to its specific recognition of antibody and molecular imprinted polymers and the signal amplification of AuNPs, the sensor had good selectivity and sensitivity toward OVA and a low detection limit of 3.0 fg/mL. The sensor also had excellent stability and could satisfactorily detect OVA in real red wine samples.

Gold Nanomaterials-Based Electrochemical Sensors and Biosensors for Phenolic Antioxidants Detection: Recent Advances

Antioxidants play a central role in the development and production of food, cosmetics, and pharmaceuticals, to reduce oxidative processes in the human body. Among them, phenolic antioxidants are considered even more efficient than other antioxidants. They are divided into natural and synthetic. The natural antioxidants are generally found in plants and their synthetic counterparts are generally added as preventing agents of lipid oxidation during the processing and storage of fats, oils, and lipid-containing foods: All of them can exhibit different effects on human health, which are not always beneficial. Because of their relevant bioactivity and importance in several sectors, such as agro-food, pharmaceutical, and cosmetic, it is crucial to have fast and reliable analysis Rmethods available. In this review, different examples of gold nanomaterial-based electrochemical (bio)sensors used for the rapid and selective detection of phenolic compounds are analyzed and discussed, evidencing the important role of gold nanomaterials, and including systems with or without specific recognition elements, such as biomolecules, enzymes, etc. Moreover, a selection of gold nanomaterials involved in the designing of this kind of (bio)sensor is reported and critically analyzed. Finally, advantages, limitations, and potentialities for practical applications of gold nanomaterial-based electrochemical (bio)sensors for detecting phenolic antioxidants are discussed.