Application of nanotechnology based-biosensors in analysis of wine compounds and control of wine quality and safety: A critical review

Recent advances in nanomaterial-based optical biosensors for food safety applications: Ochratoxin-A detection, as case study

Global population growth tremendously impacts the global food industry, endangering food safety and quality. Mycotoxins, particularly Ochratoxin-A (OTA), emerge as a food chain production threat, since it is produced by fungus that contaminates different food species and products. Beyond this, OTA exhibits a possible human toxicological risk that can lead to carcinogenic and neurological diseases. A selective, sensitive, and reliable OTA biodetection approach is essential to ensure food safety. Current detection approaches rely on accurate and time-consuming laboratory techniques performed at the end of the food production process, or lateral-flow technologies that are rapid and on-site, but do not provide quantitative and precise OTA concentration measurements. Nanoengineered optical biosensors arise as an avant-garde solution, providing high sensing performance, and a fast and accurate OTA biodetection screening, which is attractive for the industrial market. This review core presents and discusses the recent advancements in optical OTA biosensing, considering engineered nanomaterials, optical transduction principle and biorecognition methodologies. Finally, the major challenges and future trends are discussed, and current patented OTA optical biosensors are emphasized for a particular promising detection method.

A microdots array-based fluoremetric assay with superwettability profile for simultaneous and separate analysis of iron and copper in red wine

A microdots array-based fluoremetric method with superwettability profile has been developed for the simultaneous and separate detection of Fe³⁺ and Cu²⁺ ions in red wine samples. A wettable micropores array was initially designed with high density by using polyacrylic acid (PAA) and hexadecyltrimethoxysilane (HDS), followed by the NaOH etching route. Zinc metal organic frameworks (Zn-MOFs) were fabricated as the fluorescent probes to be immobilized into the micropores array to obtain the fluoremetric microdots array platform. It was found that the fluorescence of Zn-MOFs probes could decrease significantly in the presence of Fe³⁺ and/or Cu²⁺ ions towards their simultaneous analysis. Yet, the specific responses to Fe³⁺ ions could be expected if using histidine to chelate Cu²⁺ ions. Moreover, the developed Zn-MOFs-based microdots array with superwettability profile can enable the accumulation of targeting ions from the complicated samples without any tedious pre-processing. Also, the cross-contamination of different samples droplets can be largely avoided so as to facilitate the analysis of multiple samples. Subsequently, the feasibility of simultaneous and separate detection of Fe³⁺ and Cu²⁺ ions in red wine samples was demonstrated. Such a design of microdots array-based detection platform may promise the wide applications in analyzing Fe³⁺ and/or Cu²⁺ ions in the fields of food safety, environmental monitoring, and medical diseases diagnostics.

Nanotechnology: A Revolution in Modern Industry

Nanotechnology, contrary to its name, has massively revolutionized industries around the world. This paper predominantly deals with data regarding the applications of nanotechnology in the modernization of several industries. A comprehensive research strategy is adopted to incorporate the latest data driven from major science platforms. Resultantly, a broad-spectrum overview is presented which comprises the diverse applications of nanotechnology in modern industries. This study reveals that nanotechnology is not limited to research labs or small-scale manufacturing units of nanomedicine, but instead has taken a major share in different industries. Companies around the world are now trying to make their innovations more efficient in terms of structuring, working, and designing outlook and productivity by taking advantage of nanotechnology. From small-scale manufacturing and processing units such as those in agriculture, food, and medicine industries to larger-scale production units such as those operating in industries of automobiles, civil engineering, and environmental management, nanotechnology has manifested the modernization of almost every industrial domain on a global scale. With pronounced cooperation among researchers, industrialists, scientists, technologists, environmentalists, and educationists, the more sustainable development of nano-based industries can be predicted in the future.

A Selective Fluorescent l-Lactate Biosensor Based on an l-Lactate-Specific Transcription Regulator and Förster Resonance Energy Transfer

Selective detection of l-lactate levels in foods, clinical, and bacterial fermentation samples has drawn intensive attention. Many fluorescent biosensors based on non-stereoselective recognition elements have been developed for lactate detection. Herein, the allosteric transcription factor STLldR from Salmonella enterica serovar Typhimurium LT2 was identified to be stereo-selectively respond to l-lactate. Then, STLldR was combined with Förster resonance energy transfer (FRET) to construct a fluorescent l-lactate biosensor FILLac. FILLac was further optimized by truncating the N- and C-terminal amino acids of STLldR between cyan and yellow fluorescent proteins. The optimized biosensor FILLac_10N0C exhibited a maximum emission ratio change (ΔR_max) of 33.47 ± 1.91%, an apparent dissociation constant (K_d) of 6.33 ± 0.79 μM, and a limit of detection of 0.68 μM. FILLac_10N0C was applied in 96-well microplates to detect l-lactate in bacterial fermentation samples and commercial foods such as Jiaosu and yogurt. The quantitation results of FILLac_10N0C exhibited good agreement with that of a commercial l-lactate biosensor SBA-40D bioanalyzer. Thus, the biosensor FILLac_10N0C compatible with high-throughput detection may be a potential choice for quantitation of l-lactate in different biological samples.

A colourimetric fluorescent probe for the sensitive detection of total iron in wine

As the iron content of wine affects the wine quality, a highly selective and simple detection method is needed to detect the iron content in wine. A colourimetric fluorescent probe (BTBAP probe) for the detection of total iron in wine was developed. The quantitative range of Fe^2+/3+ content detected with the probe was 0 to 200 μM with a limit of detection (LOD) of 1.16 μM. After 10 min of Fe^2+/3+ addition, the luminescence intensity of the BTBAP probe solution gradually decreased with increasing Fe^2+/3+ concentration. Moreover, the B and G values of the luminescence photos were linearly related to the concentration of Fe^2+/3+ (0-200 μM). BTBAP probe was successfully applied for rapid determination of the Fe^2+/3+ concentration of wine. This work demonstrates that BTBAP probe is an excellent tool for rapid determination of the total iron content of wine using only a smartphone and no other professional equipment.

Disposable Microchamber with a Microfluidic Paper-Based Lid for Generation and Membrane Separation of SO2 Gas Employing an In Situ Electrochemical Gas Sensor for Quantifying Sulfite in Wine

This work presents a fully disposable microchamber for gas generation of a sample solution. The microchamber consists of a cylindrical well-reactor and a paper-based microfluidic lid (μFluidic lid), which also serves as the reagent loading and dispensing unit. The base of the reactor consists of a hydrophobic membrane covering an in-house graphene electrochemical gas sensor. Fabrication of the gas sensor and the three-layer μFluidic lid is described. The μFluidic lid is designed to provide a steady addition of the acid reagent into the sample solution instead of liquid drops from a disposable syringe. There are three steps in the procedure: (i) acidification of the sample in the reactor to generate SO₂ gas by the slow dispensing of the acid reagent from the μFluidic lid, (ii) diffusion of the liberated SO₂ gas through the hydrophobic membrane at the base of the reactor, and (iii) in situ detection of SO₂ by cathodic reduction at the graphene electrode. The device was demonstrated for quantitation of the sulfite preservative in wine without heating or stirring. The selectivity of the analysis is ensured by the combination of the gas-diffusion membrane and the selectivity of the electrochemical sensor. The linear working range is 2-60 mg L^-1 SO₂, with a limit of detection (3SD of intercept/slope) of 1.5 mg L^-1 SO₂. This in situ method has the shortest analysis time (8 min per sample) among all voltammetric methods that detect SO_2(g) via membrane gas diffusion.

Review of the Analytical Methods Based on HPLC-Electrochemical Detection Coupling for the Evaluation of Organic Compounds of Nutritional and Environmental Interest

This review would like to show the state of the art regarding the coupling of High-Performance Liquid Chromatography (HPLC) with Electrochemical Detection (ED). Since a universal detector for HPLC is not available, the electrochemical detection methods, thanks to their versatility and specificity, are competitive with respect to the detectors currently used. The papers present in literature on HPLC-ED technique are analyzed and discussed: for example, they regard the development of analytical determinations of resveratrol, rosmarinic acid, aromatic heterocyclic amines and glyphosate in food matrices such as meat, aromatic plants, vegetables, fruit and tomato juices. These papers show that electrochemical sensors used as detectors for HPLC can offer better sensitivity values than other detectors. Furthermore, the use of specific working potentials allows avoid matrix interferences to be avoided by almost exclusively determining the analytes of interest. It should be underlined that HPLC-ED methods have a selectivity that allows for limitation of the sample preparation and clean-up procedures to a minimum, making them quick and easy to apply. In addition, these methods offer advantages such as the possibility of direct analysis, that derivatization is often not necessary, the cost-effectiveness of the instrumentation and the possibility of regenerating the electrodes which allows numerous analyses in succession.

Electrochemical Sensors Coupled with Multivariate Statistical Analysis as Screening Tools for Wine Authentication Issues: A Review

Consumers are increasingly interested in the characteristics of the products they consume, including aroma, taste, and appearance, and hence, scientific research was conducted in order to develop electronic senses devices that mimic the human senses. Thanks to the utilization of electroanalytical techniques that used various sensors modified with different electroactive materials coupled with pattern recognition methods, artificial senses such as electronic tongues (ETs) are widely applied in food analysis for quality and authenticity approaches. This paper summarizes the applications of electrochemical sensors (voltammetric, amperometric, and potentiometric) coupled with unsupervised and supervised pattern recognition methods (principal components analysis (PCA), linear discriminant analysis (LDA), partial least square (PLS) regression, artificial neural network (ANN)) for wine authenticity assessments including the discrimination of varietal and geographical origins, monitoring the ageing processes, vintage year discrimination, and detection of frauds and adulterations. Different wine electrochemical authentication methodologies covering the electrochemical techniques, electrodes types, functionalization sensitive materials and multivariate statistical analysis are emphasized and the main advantages and disadvantages of using the proposed methodologies for real applications were concluded.

Evaluation of trans-resveratrol level in grape wine using laser-induced porous graphene-based electrochemical sensor

trans-Resveratrol (TRA), is one of the indicators to evaluate the quality of red wines. In this study, a novel flexible electrochemical sensor using direct laser-induced graphene (LIG) technique that transforms the commercial Kapton tape into three-dimensional (3D) porous graphene was developed for sensitive detection of TRA molecules in red wines. For the first time, the strategy of 'double layer' (Kapton/polyimide) was employed to obtain the LIG with undamaged shape and excellent electrical properties. The mechanism of heat absorption and dissipation of laser-induced process was investigated in detail. The prepared electrochemical sensor with excellent repeatability, stability, reproducibility, and reliability, appears an excellent linear response within the TRA concentration range from 0.2 to 50 μmol L^-1 and a low limit of detection (LOD) of 0.16 μmol L^-1. Furthermore, the developed sensor can be applied for the evaluation of TRA level in red wines and grape skins with a satisfactory result. The sensor may be potential in analysis of active compounds in food or environmental samples.