Immobilizing diamine oxidase on electroactive phase-change microcapsules to construct thermoregulatory smart biosensor for enhancing detection of histamine in foods

An integrated colorimetric biosensing platform containing microneedle patches and aptasensor for histamine monitoring in seafood

Excessive histamine in spoiled seafood poses considerable health hazards to consumers, yet its detection is challenging due to complicated sample preparation and detection methodologies. Herein, an integrated colorimetric platform containing Poly (vinyl alcohol) (PVA)/hyaluronic acid (HA) microneedle patches-assisted extraction and aptasensor-based detection was reported. The developed PVA/HA microneedle patches facilitated on-site histamine extraction from seafood through a two-minute press-and-peel procedure. To enhance detection efficacy, strategies for generating high-affinity aptamers with specific terminal-fixed structures and constructing AuNPs@FeP-chitosan oligosaccharide (COS) nanozyme boosting catalytic efficiency were proposed. Utilizing the aptamer HIS3-T2 in conjunction with the nanozyme, a colorimetric aptasensor was developed. Integrated with the patches, the aptasensor achieved high sensitivity and selectivity, detecting histamine within a range of 2-800 nM with a limit of detection (LOD) of 1.89 nM. Validated on real-world salmon and shrimp samples, this integrated system promises rapid and accurate histamine monitoring, offering great reference for similar applications in food quality control.

Recent progress in nanomaterial-based electrochemical biosensors for hydrogen peroxide detection & their biological applications

The electrochemical biosensor has brought a paradigm shift in the field of sensing due to its fast response and easy operability. The performance of electrochemical sensors can be modified by coupling them with various metal oxides, nanomaterials, and nanocomposites. Hydrogen peroxide is a short-lived reactive oxygen species that plays a crucial role in various physiological and biological processes. Therefore, its monitoring is of paramount importance. With this, the research fraternity has developed various nanomaterial-based superlative sensors that have enhanced the sensing performance towards H2O2 in terms of sensitivity, detection limit, and linear range. The integration of nanocomposite materials has allowed for the synergistic combination of different components, leading to improved sensor stability, selectivity, and detection limits. The precious metal alloys, metal oxides, semiconductor nanomaterials, carbon cloth, multi-walled carbon nanotubes, graphene oxide, and nanoparticles demonstrate effective catalytic performance for detecting H2O2 electrochemically. These advanced materials possess extraordinary properties and structures, rendering them highly advantageous for diverse applications. These biosensors aid in monitoring H2O2 levels secreted by MCF-7, HeLa cells, NIH-3T3, and A549 cells in real-time. Further, this type of biosensor identified alterations in H2O2 levels in the lungs, bronchoalveolar lavage fluid (BALF) of mice with pulmonary fibrosis, activated hepatic stellate cells, and the livers of mice with liver fibrosis. The current review highlights the recent advancements in compositions, morphology, limit of detection, sensitivity, biological applications, etc. properties of the electrochemical biosensors for H2O2 detection.

Simple design of fluorescein-based probe for rapid and in situ visual monitoring of histamine levels in food spoilage

With the emergence of numerous food safety problems, rapid and accurate detection of histamine in food spoilage remains a challenge. To this end, we developed a simple design and easy synthesis of fluorescein-based probe FCHO to achieve specific and rapid (<1 s) quantitative detection of histamine through "imine formation" reaction. Significant enhanced fluorescence signal in response to histamine enabled our probe with high sensitivity as low as 51 nM. Utilizing the visualized fluorescence color changes of the probe as histamine increasing, we combined it with paper-based test chip to construct a color-resolved and highly selective recognition system. In addition, our proposed probe has been successfully used to visually imaging histamine changes in fish samples. Finally, for the first time, we have proved it possesses reliable ability to directly in situ imaging the distribution of histamine in whole spoiled fish. Thus, our strategy will provide great potential for monitoring food spoilage.

A simple and reliable interenzyme distance regulation strategy based on a DNA quadrangular prism scaffold for ultrasensitive ochratoxin A detection

Developing sensitive and accurate Ochratoxin A (OTA) detection methods is essential for food safety. Herein, a simple and reliable strategy for regulating interenzyme distance based on a rigid DNA quadrangular prism as a scaffold was proposed to establish a new electrochemical biosensor for ultrasensitive detection of OTA. The interenzyme distances were precisely adjusted by changing the sequences of the hybridized portions of hairpins SH1 and SH2 to the DNA quadrangular prism, avoiding the complexity and instability of the previous DNA scaffold-based enzyme spacing adjustment strategies. The electrochemical biosensor constructed at the optimal interenzyme distance (10.4 nm) achieved sensitive detection of OTA in a dynamic concentration range from 10 fg/mL to 250 ng/mL with a detection limit of 3.1 fg/mL. In addition, the biosensor was applied to quantify OTA in real samples, exhibiting great application potential in food safety.

Recent advances in the use of composite titanium dioxide nanomaterials in the food industry

Titanium dioxide (TiO2 ) nanomaterials have attracted significant attention due to their good biocompatibility and potential for multifunctional applications. In the last few years, there has been growing interest in the use of TiO2 nanomaterials in the food industry. However, a systematic review of the synthesis methods, properties, and applications of TiO2 nanomaterials in the food industry is lacking. In this review, we provide a summary of the synthesis and properties of TiO2 nanomaterials and their composites, with a focus on their applications in the food industry. We also discuss the potential benefits and risks of using TiO2 nanomaterials in food applications. This review aims to promote food innovation and improve food quality and safety.

Spotlight on autochthonous microbiota, morpho-textural characteristics, and volatilome of a traditional Polish cold-smoked raw sausage

The aim of the present study was to obtain information on the bacterial diversity of traditional Polish cold-smoked raw sausages (Kiełbasa polska wędzona) manufactured by two artisanal producers using different selective growth media and a metataxonomic analysis. Physico-chemical and morpho-textural characteristics were also carried out, together with Microextraction-Gas Chromatography/Mass Spectrometry (HS-SPMEGC/MS) to study the volatile organic compounds (VOCs). The results overall obtained allowed a picture of the microbiota, the morpho-textural characteristics, and the volatilome of traditional Polish cold-smoked raw sausages (Kiełbasa polska wędzona) to be drawn for the first time. In more detail, viable counting revealed active populations of presumptive lactobacilli, enterococci, coagulase-negative cocci, and a few spoilage microorganisms typically occurring in raw meat products. The metataxonomic analysis revealed the dominance of Latilactobacillus sakei occurring with a relative frequency between 77% and 89%. Pediococcus pentosaceus, Weissella hellenica, and Leuconostoc carnosum were detected among the minority taxa. In the sausages herein studied, no histamine levels of concern were detected. The Principal Component Analysis (PCA) performed on the Amplicon Sequence Variants (ASVs) did not show significant differences in the microbiota composition among producers. The HS-SPMEGC/MS analysis allowed the detection and identification of more than 90 volatile components belonging to ten main classes, namely: aldehydes, ketones, esters and acetates, acids, alcohols, phenols, furans, sulphur compounds, terpenoids, and benzene derivatives. The detected VOCs originated from spices, smoke, and microbial metabolism. The PCA of volatile compounds allowed differences between the sausage samples of the two producers to be identified.

Immobilization of Enzyme Electrochemical Biosensors and Their Application to Food Bioprocess Monitoring

Electrochemical biosensors based on immobilized enzymes are among the most popular and commercially successful biosensors. The literature in this field suggests that modification of electrodes with nanomaterials is an excellent method for enzyme immobilization, which can greatly improve the stability and sensitivity of the sensor. However, the poor stability, weak reproducibility, and limited lifetime of the enzyme itself still limit the requirements for the development of enzyme electrochemical biosensors for food production process monitoring. Therefore, constructing sensing technologies based on enzyme electrochemical biosensors remains a great challenge. This article outlines the construction principles of four generations of enzyme electrochemical biosensors and discusses the applications of single-enzyme systems, multi-enzyme systems, and nano-enzyme systems developed based on these principles. The article further describes methods to improve enzyme immobilization by combining different types of nanomaterials such as metals and their oxides, graphene-related materials, metal-organic frameworks, carbon nanotubes, and conducting polymers. In addition, the article highlights the challenges and future trends of enzyme electrochemical biosensors, providing theoretical support and future perspectives for further research and development of high-performance enzyme chemical biosensors.

Recent Advances in Electrochemical Enzyme-Based Biosensors for Food and Beverage Analysis

Food analysis and control are crucial aspects in food research and production in order to ensure quality and safety of food products. Electrochemical biosensors based on enzymes as the bioreceptors are emerging as promising tools for food analysis because of their high selectivity and sensitivity, short analysis time, and high-cost effectiveness in comparison to conventional methods. This review provides the readers with an overview of various electrochemical enzyme-based biosensors in food analysis, focusing on enzymes used for different applications in the analysis of sugars, alcohols, amino acids and amines, and organic acids, as well as mycotoxins and chemical contaminants. In addition, strategies to improve the performance of enzyme-based biosensors that have been reported over the last five years will be discussed. The challenges and future outlooks for the food sector are also presented.

Spectro-Electrochemical Properties of A New Non-Enzymatic Modified Working Electrode Used for Histamine Assessment in the Diagnosis of Food Poisoning

We successfully prepared a non-enzymatic sensor based on a graphene-thiophene composite for histamine detection. The self-assembling properties of the thiophene onto Au support and the high electrical conductivity of graphene encouraged the choice of this type of composite. The composite was deposited via electrochemical polymerization onto the Au layer of a screen-printed microelectrode. The electropolymerization and electrochemical detection of histamine were both achieved by cyclic voltammetry. Two types of electrolytes were used for the electrochemical detection: (a) phosphate buffer solution (PBS), which showed low-intensity redox peaks for histamine; and (b) trichloroacetic acid (TCA) 0.01 M, which showed improved results over PBS and did not damage the microelectrode. For the concentration range of 100-200 mg/kg, the sensor shows a linear regression pattern for the oxidation peak fitted on the equation Ipa = 123.412 + 0.49933 ×x, with R2 = 0.94178. The lowest limit of detection was calculated to be 13.8 mg/kg and the limit of quantification was calculated at 46 mg/kg. These results are important since by monitoring the amount of histamine in a food product, early onset of spoilage can be easily detected, thus reducing foodborne poisoning and food waste (by recycling products that are still edible).