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The accurate monitoring of lactate level is very important in the fields of food quality and sport. In the present work, an effective sensor was introduced for lactate monitoring in food and in human bio-fluid. The non-enzymatic electrochemical sensor was fabricated by bulk modification of a simple carbon paste electrode (CPE) with iron-copper ferricyanide (ICF) catalyst and room temperature ionic liquid (IL). The lactate sensing capabilities of the suggested sensor are significantly enhanced due to the combination of the high conductivity of IL and the improved catalytic properties of the ICF modifier. The chronoamperometric response measurements of the ICF-IL-CPE demonstrated a high sensitivity towards lactate across a broad linear range of 20 to 1000 µM, with a correlation coefficient of R2 = 0.999. This sensor also exhibited a detection limit of 4.5 µM, a reproducibility of 3.9% relative standard deviation, and a stability of 95.8% over a period of five weeks. The suggested ICF-IL-CPE depicted minimal background interference against common interfering species. This makes it a highly promising tool for accurately measuring lactate concentrations in various samples including saliva from athletes and cow milk. [ABSTRACT FROM AUTHOR]

Sunset Yellow FCF (E110) is a widely utillized azo synthetic food colorant due to its appealing hue and significant market popularity. Attributable to the health risks caused by excessive usage of Sunset Yellow, ecologically safe method for quantifying the same are to be prioritized. The purpose of this study is to develop and validate an Analytical Quality by Design based eco-friendly HPLC method followed by ultrasound assisted extraction of food samples and confirmation of them using FTIR. To comply with the requirements of green analytical chemistry ethanol was utilized because of its environmental friendliness nature. The chromatographic parameters were optimized using rotatable central composite designs (rCCD) whereas the separation was performed on a Phenomenex column (C18, 250 mm × 4.6 mm, i.d 5 μm) using a mobile phase consisting of a 34.4:65.6 (v/v) mixture of ethanol and acetate buffer at flow rate of 1.1 ml/min with detection wavelength of 510 nm. The elution of Sunset Yellow occurred after 2.133 min. The method was thoroughly validated and tested as part of the forced degradation investigation to ascertain its stability-indicating properties. When evaluating the extent of greenness, the Green Analytical Procedure Index, Analytical Eco Scale and AGREE metrics tools yielded the best findings. The blueness and whiteness of the method was assessed by Blue Applicability Grade Index and Red-Green-Blue 12 (RGB 12) algorithm respectively with a high score which shows high practicality, cost effectiveness and ecofriendliness of the method.

Simple and sensitive determination of total antioxidant capacity (TAC) in food samples is highly desirable. In this work, an electrochemical platform was established based on a silica nanochannel film (SNF)-modified electrode, facilitating fast and highly sensitive analysis of TAC in colored food samples. SNF was grown on low-cost and readily available tin indium oxide (ITO) electrode. Fe3+-phenanthroline complex-Fe(III)(phen)3 was applied as the probe, and underwent chemical reduction to form Fe2+-phenanthroline complex-Fe(II)(phen)3 in the presence of antioxidants. Utilizing an oxidative voltage of +1 V, chronoamperometry was employed to measure the current generated by the electrochemical oxidation of Fe(II)(phen)3, allowing for the assessment of antioxidants. As the negatively charged SNF displayed remarkable enrichment towards positively charged Fe(II)(phen)3, the sensitivity of detection can be significantly improved. When Trolox was employed as the standard antioxidant, the electrochemical sensor demonstrated a linear detection range from 0.01 μM to 1 μM and from 1 μM to 1000 μM, with a limit of detection (LOD) of 3.9 nM. The detection performance is better that that of the conventional colorimetric method with a linear de range from 1 μM to 40 μM. Owing to the anti-interfering ability of nanochannels, direct determination of TAC in colored samples including coffee, tea, and edible oils was realized. [ABSTRACT FROM AUTHOR]

Sulfites play imperative roles in food crops and food products, serving as sulfur nutrients for food crops and as food additives in various foods. It is necessary to develop an effective method for the on-site quantification of sulfites in food samples. Here, 7-(diethylamino) quinoline is used as a fluorescent group and electron donor, alongside the pyridinium salt group as an electron acceptor and the C=C bond as the sulfite-specific recognition group. We present a novel fluorescent sensor based on a mechanism that modulates the efficiency of intramolecular charge transfer (ICT), CY, for on-site quantitative measurement of sulfite in food. The fluorescent sensor itself exhibited fluorescence in the near-infrared light (NIR) region, effectively minimizing the interference of background fluorescence in food samples. Upon exposure to sulfite, the sensor CY displayed a ratiometric fluorescence response (I447/I692) with a high sensitivity (LOD = 0.061 μM), enabling accurate quantitative measurements in complex food environments. Moreover, sensor CY also displayed a colorimetric response to sulfite, making sensor CY measure sulfite in both fluorescence and colorimetric dual-signal modes. Sensor CY has been utilized for quantitatively measuring sulfite in red wine and sugar with recoveries between 99.65% and 101.90%, and the RSD was below 4.0%. The sulfite concentrations in live cells and zebrafish were also monitored via fluorescence imaging. Moreover, the sulfite assimilated by lettuce leaves was monitored, and the results demonstrated that excessive sulfite in leaf tissue could lead to leaf tissue damage. In addition, the sulfate-transformed sulfite in lettuce stem tissue was tracked, providing valuable insights for evaluating sulfur nutrients in food crops. More importantly, to accomplish the on-site quantitative measurement of sulfite in food samples, a portable sensing system was prepared. Sensor CY and the portable sensing system were successfully used for the on-site quantitative measurement of sulfite in food. [ABSTRACT FROM AUTHOR]

Nanoparticle-based magnetic solid phase microextraction (MSPME) has advanced in heavy metal ion concentration and speciation in recent years. This comprehensive review covers the latest developments in this field and their application to complex food samples. The review begins with conventional MSPE methods' challenges and constraints, then examines off-line and online MSPE formats. Later sections of the review examine solid phase extraction's (SPE) use of magnetized inorganic nanomaterials. These include magnetic silica, alumina, titania, and layered double oxides. Magnetized carbonaceous nanomaterials, such as magnetic graphene and/or graphene oxides, carbon nanotubes, and carbon nitrides, also belong to this study. The study describes how magnetized organic polymers-non-imprinted and ion-imprinted improved SPE. Magnetized metal-organic frameworks (MOF), ionic liquids, and biosorbents are also covered briefly. Each section carefully examines nanomaterials' selectivity, sorption capacity, mechanisms of sorption, and synthesis routes. Nanomaterials are becoming key sorbents for toxic heavy metal extraction from food samples. Carbon nanomaterials (CNMs), magnetic nanoparticles (MNPs), nano-imprinted polymers (NIPs), nano-based metal-organic frameworks (N-MOFs), and silica nanoparticles (SiNPs) are leading preconcentration methods due to their high surface area, selectivity, rapid adsorption kinetics, and food contamination capture efficiency. The review emphasizes the importance of SPE and SPME, enhanced by nanomaterial sorbents and summarizes nanomaterialinfused solid phase extraction strategies and their impact on heavy metal extraction from food matrices. The review examines a variety of nanomaterials and their complex use to improve selectivity, extraction efficiency, and future research in this crucial area. [ABSTRACT FROM AUTHOR]

Here, an enzyme-free lateral flow aptasensor was designed by target-induced strand-displacement effect and followed by the activation of multi-component nucleic acid enzyme (MNAzyme)-mediated cleavage to enable rapid and portable ochratoxin A (OTA) detection. The substrate was prepared as an oligonucleotide strand modified with magnetic beads (MB) and human chorionic gonadotropin (hCG). The interaction of OTA with the aptamer induces the release of blocking DNA, which hybridized with three separated subunits of DNA, forming a sequence-specific MNAzyme catalytic core. This core subsequently initiated an enzyme-free MNAzyme cleavage reaction in the presence of the Mg2+ cofactor, cleaving a special substrate and releasing both the incomplete MNAzyme catalytic core and hCG-DNA probe. The incomplete MNAzyme catalytic core was then recognized by substrates once again, triggering a cascade recycling cleavage and resulting in the generation of a larger number of hCG-DNA probes. After magnetic enrichment, the free hCG-DNA probes flow through the pregnancy test strip (PTS) to the T line, generating a colorimetric readout that unequivocally confirms the presence of the target OTA. This work leverages the efficient enzyme-free cleavage amplification of MNAzyme and the PTS-based portable detection device, presenting a biosensing strategy with significant potential for sensitive and portable OTA detection. This method exhibited remarkable sensitivity and selectivity for OTA detection, boasting a detection limit of 5 nM. The present study successfully demonstrated the practical application of this method on real samples, offering a viable alternative for rapid and portable detection of mycotoxins. [ABSTRACT FROM AUTHOR]

Sulfites play imperative roles in food crops and food products, serving as sulfur nutrients for food crops and as food additives in various foods. It is necessary to develop an effective method for the on-site quantification of sulfites in food samples. Here, 7-(diethylamino) quinoline is used as a fluorescent group and electron donor, alongside the pyridinium salt group as an electron acceptor and the C=C bond as the sulfite-specific recognition group. We present a novel fluorescent sensor based on a mechanism that modulates the efficiency of intramolecular charge transfer (ICT), CY, for on-site quantitative measurement of sulfite in food. The fluorescent sensor itself exhibited fluorescence in the near-infrared light (NIR) region, effectively minimizing the interference of background fluorescence in food samples. Upon exposure to sulfite, the sensor CY displayed a ratiometric fluorescence response (I447/I692) with a high sensitivity (LOD = 0.061 μM), enabling accurate quantitative measurements in complex food environments. Moreover, sensor CY also displayed a colorimetric response to sulfite, making sensor CY measure sulfite in both fluorescence and colorimetric dual-signal modes. Sensor CY has been utilized for quantitatively measuring sulfite in red wine and sugar with recoveries between 99.65% and 101.90%, and the RSD was below 4.0%. The sulfite concentrations in live cells and zebrafish were also monitored via fluorescence imaging. Moreover, the sulfite assimilated by lettuce leaves was monitored, and the results demonstrated that excessive sulfite in leaf tissue could lead to leaf tissue damage. In addition, the sulfate-transformed sulfite in lettuce stem tissue was tracked, providing valuable insights for evaluating sulfur nutrients in food crops. More importantly, to accomplish the on-site quantitative measurement of sulfite in food samples, a portable sensing system was prepared. Sensor CY and the portable sensing system were successfully used for the on-site quantitative measurement of sulfite in food.

Electrochemical determination of melatonin in the presence of tryptophan is a challenge because of the coincidence of voltammetric signals of these compounds when executing a voltammetric technique. The new method for selective determination of melatonin based on the square wave anodic stripping voltammetry determination of an electroactive product of melatonin was suggested here. This product is produced by previously applied positive pre‐potential to a carbon paste electrode, immersed in the test solution. By this means, the electrochemical signal of melatonin was separated effectively from that of tryptophan, making it possible to determine melatonin in the presence of a high concentration of tryptophan. The effect of important parameters on electrode performance was studied and optimized. The optimum response was obtained at pH=2 and utilizing the pre‐potential magnitude of +0.8 V, applied for 10 s. A linear relationship was found between peak current intensity and melatonin concentrations over the range of 5.00×10−7 to 8.00×10−5 mol L−1. A detection limit of 8.30×10−8 mol L−1 was calculated for the method (S/N=3). The selectivity of the method was considerably high, because of the independence of melatonin signal to the presence of higher amounts of some potentially interfering agents such as ascorbic acid, tryptophane glucose, etc. As an analytical application, the proposed sensor was used for the determination of melatonin in pharmaceutical and food samples. [ABSTRACT FROM AUTHOR]

A sensitive dual immunochromatographic test strip (dual-ICTS) was developed to detect malachite green (MG) and its metabolite, leucomalachite green (LMG), using two types of gold nanoparticles: round-shaped (red) and star-shaped (blue). The detection limits were determined to be 0.221 μg L−1 for MG and 0.214 μg L−1 for LMG, respectively. The dual-ICTS provided a cut-off value of 1.8 μg L−1 for MG and LMG detection. The dual-ICTS successfully detected MG and LMG in food samples, with recovery rates ranging from 86 % to 116 %. The dual-ICTS was evaluated by correlation analysis between the proposed assay and the well-established enzyme-linked immunosorbent assay in the MG and LMG detection. This is the first report on the development of the ICTS that can detect both MG and LMG at the same time within only 5 min, making it a sensitive and rapid tool for on-site detection. [Display omitted] • Two colored gold nanoparticles were applied as dual - color labels in ICTS. • A novel dual-ICTS was fabricated for simultaneous detection of MG and LMG. • The dual-ICTS provided a cut-off value of 1.8 μg L−1 for MG and LMG detection. • ICTS is a rapid, for on-site simultaneous detection for MG and LMG within 5 min. [ABSTRACT FROM AUTHOR]

[Display omitted] • Julolidine-coumarin based probes with varying electron acceptor unit was synthesized. • The probes displayed a striking color change when exposed to cyanide ions. • To enable real-time analysis, an Arduino electronic device was developed. • The sensor system can detect cyanide ion in food and water samples. A highly efficient system that incorporates the instantaneous visualization of the cyanide ion in water was synthesized by keeping the fluorophore system (electron donor) as a julolidine-coumarin conjugate and changing the electron acceptor unit. The probes exhibit a notable color change in normal and UV light. The probe interaction modalities are based on the ICT process. With a detection limit in the nM range, it may preferentially react with cyanide, which is less than the tolerable level of 1.9 μM. According to 1H NMR data, the probes detect cyanide ions by nucleophilic addition reaction mechanism. Furthermore, current probe successfully determines real resources, including cyanide containing cassava powder, sprouted potatoes and various water samples. Besides the test strips, an electronic Arduino device was also employed to detect the cyanide ion. As such, the developed probes exhibit outstanding practical application with respect to the cyanide ion. [ABSTRACT FROM AUTHOR]

In this study, we present a new approach utilizing Au nanodendrites (Au NDs) to modify flexible screen-printed carbon electrodes (FSPCEs), offering an efficient platform for voltammetric sensing of nitrite ions in food samples. The FSPCEs are created with gold leaf-like nanodendrites through a simple, one-step electrochemical deposition process. The direct growth of these Au NDs occurs efficiently on the carbon-paste electrode, eliminating the need for binders or additional reducing agents and organic solvents, owing to the aforementioned matrix. The modified electrodes serve as promising sensing platforms for nitrite detection. The outcomes demonstrated that a significant amount of AuNPs with dendritic morphologies were dispersed throughout the FSPCE.These novel flexible electrodes act as effective electrocatalyst for NO 2 − oxidation due to their large electrochemical active surface area (ECSA), well-dispersed Au nanostructures, and high electrical conductivity. The optimized sensor exhibits a wide linear response range from 0.02 to 5.8 µM, with 1.0 nM limit of detection, an impressive sensitivity of 52.529 µA µM−1 cm−2 and a quick current response time (< 3 s) towards nitrite ions. Additionally, the suggested sensor demonstrates high selectivity, reproducibility, and stability. Furthermore, the FSPCEs are evaluated for their ability to selectively detect nitrite ions in various food samples such as tap water, drinking water, milk, and fruit juices, comparing the results with standard methods in real sample analysis. The fabricated sensors show promising potential for practical applications in food and environmental analysis. Consequently, Au NDs@FSPCE electrode emerged to be a novel platform for NO 2 − electrochemical detection. Because of their great affinity for analytical substances in solutions, gold nanodendrites supported on flexible screen-printed carbon electrodes (FSPCEs) are very useful for electrode modifications. Their increased effective surface area, which greatly raises the electrode's sensitivity and specificity for a range of analytical applications, is responsible for their high affinity. [Display omitted] [ABSTRACT FROM AUTHOR]

Food adulterants are substances added to food products to improve their weight and appearance and reduce costs. However, the use of these substances deteriorates the quality of food products and results in a decrease in nutritional value. For this reason, situations that negatively affect the health of consumers occur. Microfluidic paper-based analytical devices (μPADs) have gained popularity as miniaturized, portable, highly sensitive, accurate, and affordable detection platforms. μPADs are preferred as advantageous platforms for the determination of food adulterants in foods, thanks to their on-site analysis and simultaneous determination of multiple analytes features. Therefore, μPADs provide fast and reliable results in food safety. In this review, the selection of paper and method for the fabrication of μPADs, as well as the determination of the signal readout mode, are briefly mentioned. In addition, the sample preparation process before the use of PADs is also mentioned. The most current applications of μPADs in determining food adulteration are applied sample, method, linear range, LOD, etc., evaluated in terms of parameters. This review also sheds light on commercial practices by discussing the most prominent studies in the last three years. • μPAD-based analytical device approaches for the detection of food adulteration. • A comprehensive overview of food adulteration practices. • The place of μPADs in food applications. • Extensive investigation to produce of μPADs. [ABSTRACT FROM AUTHOR]

Sulfur dioxide and its derivatives (HSO 3 −/SO 3 2-) play a crucial role in maintaining the redox balance of biological systems. Therefore, the development of effective detection methods for sulfur dioxide and its derivatives is of paramount importance. Herein, a novel fluorescent probe, QLN , was designed and synthesized using small molecule quinoline, demonstrating the capacity to recognize HSO 3 − through Michael addition reaction. The probe QLN displayed good selectivity and anti-interference capabilities for HSO 3 − recognition, effectively operating within a wide pH range (5–9) and exhibiting a rapid response time (<5 s). Practical applications revealed the potential of probe QLN for detecting HSO 3 − in living cells and food samples. A new fluorescence 'turn-on' probe QLN for HSO 3 − recognition in an aqueous media utilizing ICT effect has been developed. [Display omitted] • Probe QLN has high selectivity and sensitivity for the detection of HSO 3 −. • Probe QLN can detect HSO 3 − via color deepening and fluorescence "turn on" dual response. • Probe QLN can be attached to silica gel plate for qualitative detection of SO 2 gas. • Probe QLN can be based on hydrogel-based kits to detect the content of HSO 3 − in food samples. • Probe QLN can image endogenous and exogenous HSO 3 − in MCF-7 cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • NIR photothermal lens spectrometer (PTLS) used for determination phosphate ions. • NIR PTLS is highly sensitive to phosphate with the detectability amount to 33 pg. • Phosphate ions can be analyzed by using PTLS in beverage and blood serum samples. • NIR PTLS with microfluidic cell can be used for phosphate detection in 50 µL samples. In this work, photothermal lens spectrophotometer (PTLS) with crossed-beam configuration pumped by a laser diode (850 nm) was used for determination of soluble phosphorus exists mainly in the form of orthophosphate (PO 4 3−) in nonalcoholic beverage and human blood serum samples. The determination was carried out after complexation reaction between blue molybdenum and phosphate in aqueous solution. UV–vis spectrophotometry was used by measuring absorption in the near infrared region (815 nm) for optimizing the complex formation time, concentrations of reducing agent and sulfuric acid. The UV–vis absorption measurements showed that the calibration curve was obtained in the concentration ranges of 0.5–80 mg L−1 with a linear correlation coefficient of 0.98 and a detection limit of 0.2 mg L−1. Then, PTLS at a wavelength of 850 nm after optimizing the device conditions (flow rate, excitation laser power and interrupting frequency) was used for phosphate determination. The calibration curve in the concentration range of 11–1000 µg L−1 has a correlation coefficient of 0.98 and a detection limit of 4 µg L−1. The achieved detection limit was about 50 times better than NIR absorption spectrometry using a conventional 1 cm sample cell. In PTLS with the 3 μL microfluidic cell experimental detectability amount of phosphate is 33 picogram, while in UV–vis-NIR method this amount is 1.5 µg. [ABSTRACT FROM AUTHOR]

[Display omitted] • Quasi-hydrophobic DES for simultaneous extraction of polar and non-polar analytes. • Wide range of mathematical models to confirm experimental results. • Quasi-hydrophobic DES provide versatility in the extraction of a wide range of dyes. • The first automated procedure for determination of polar and non-polar dyes. In this work, quasi-hydrophobic deep eutectic solvents were used for the first time for the efficient extraction of both polar (Sunset Yellow FCF (E 110), Azorubine (E122), Ponceau 4R (E124)) and non-polar (Sudan I, Sudan II, Sudan III) dyes from food products at the same time. These solvents were made from polar and nonpolar components, which made it possible to extract analytes of various natures. To automate the technique, a flow analysis method was used, which increases the speed and reliability of determining analytes in food samples. For a detailed study of extraction mechanisms, various process modeling methods were used. The proposed DES-based method addresses the limitations of traditional extraction methods, offering a more robust and efficient solution for food analysis. Validation of the method has demonstrated high precision, accuracy and extraction efficiency, making it a promising tool for regulatory compliance and consumer safety in the food industry. The following analytical characteristics were achieved: the limits of detection were 0.03–0.13 mg L−1, limits of quantification were 0.09–0.44 mg L−1, an extraction recovery exceeding 85 %, a linear range was from 1 to 100 mg L−1, and a relative standard deviation ranging from 2 % to 10 %. The experiments were confirmed by both Conductor Like Screening Model-Segment Activity Coefficient (COSMO-SAC) and the Non-Covalent Interaction using the Reduced Density Gradient of the DES-dye system in aqueous media. [ABSTRACT FROM AUTHOR]

The emission of venenous sulfur dioxide (SO 2) and its derivatives from industrial applications such as coking, transportation and food processing has caused great concern about public health and environmental quality. Probes that enable sensitivity and specificity to detect SO 2 derivatives play a crucial role in its regulations and finally mitigating its environmental and health impacts, but fluorescent probes that can accurately, rapidly and on-site detect SO 2 derivatives in foodstuffs and environmental systems rarely reported. Herein, a near-infrared (NIR) fluorescent probe (ZTX) for the ratiometric response of bisulfite (HSO 3 −) was designed and synthesized by regulating the structure of high-performance HSO 3 − fluorescent probe SL previously reported by us based on structural analyses, theoretical calculations and related literature reports. The Michael addition reaction between the electronic-deficient C=C bond and HSO 3 − destroys ZTX 's π-conjugation system and blocks its intramolecular charge transfer (ICT) process, resulting in a significant fading of the fuchsia solution and the bluish-purple fluorescence turned light blue fluorescence. Fluorescent imaging of HSO 3 − in live animals utilizing ZTX has been demonstrated. The quantitative analysis of HSO 3 − in food samples using ZTX via a smartphone has been also successfully implemented. Simultaneously, the ZTX -based test strips were utilized to quantificationally determine HSO 3 − in environmental water samples by a smartphone. Consequently, probe ZTX could provide a new method to understand the physiopathological roles of HSO 3 −, evaluate food safety and monitor environment, and is promising for broad applications. [Display omitted] • The fluorescence probe ZTX features NIR-emitting (849 nm), large Stokes shift (326 nm) and high biocompatibility. • The quantitative determination of HSO 3 − in environmental water and actual food sampleswere realized using ZTX combined with a smartphone. • Applications of ZTX in fluorescence imaging of HSO 3 − in vivo in mouse model are successfully demonstrated. [ABSTRACT FROM AUTHOR]

The increasing demand for higher quality of wide-ranged food products lead to the overproduction of food commodities in an extremely short time. Such massive product output causes the demands on storage conditions, such as air humidity and regulation, time of storage, and temperature, to rapidly decrease. Therefore, a large variety of pathogenic microbes can be present in food commodities that can trigger a set of serious long-term health issues for human and animal beings. Nowadays, food contamination represents one of the most important worldwide issues that need to be regulated. Among all analytical methods, electrochemical aptasensors have shown to be great candidates for the fast, reliable, and ultrasensitive detection of foodborne pathogens, mainly mycotoxins, in food matrices. This work offers a complex overview of electrochemical aptasensors and their applications in food quality control. It includes modern immobilization strategies in combination with modern electroanalytical methods as detection techniques. This work presents the possibilities to create more practical and effective aptasensing devices with a high level of sensitivity, selectivity, and specificity. These innovations are brought out with a hope to be later involved in the development of miniaturized, portable, and commercially available lab-on-chip devices that would be applicable in a friendly manner for end-users. [ABSTRACT FROM AUTHOR]

Background: Acesulfame K (E950) and Saccharin Na (E954) are commonly utilized synthetic sweeteners that are added to various processed food products to improve the sweet flavor. It is essential to give priority to environmentally friendly technology while assessing them, as overuse of these sweeteners presents serious health hazards., Objective: The main aim of this study was to develop an AQbD aided ecofriendly RP-HPLC technique that can detect both Acesulfame K and Saccharin Na simultaneously incorporating green analytical chemistry (GAC) principles and white analytical chemistry (WAC); using ultrasound-assisted extraction (UAE) technique on commercial food samples., Method: The usage of ethanol was in accordance with eco-friendly ideals due to its ease of use, speed, and lack of environmental impact. Rotatable central composite designs (rCCD) was used for method optimization and a mobile phase consisting of a 50:50 (v/v) mixture of ethanol and 1% aqueous acetic acid (v/v), the separation was carried out on a Zorbax column (SB-C18, 150 × 4.6 mm, 5 µm) with a flow rate of 1 ml/min and a detection wavelength of 217 nm., Results: Acesulfame K had retention duration of 1.134 minutes and Saccharin Na of 2.134 minutes. Acesulfame K and Saccharin Na recovery rates varied among different commercially available food samples, ranging from 65-102% and 75-101%, respectively., Conclusion: At the defined operating point, the developed procedure displays conformity with the previously defined requirements for linearity, accuracy, sensitivity, and repeatability. The most accurate assessments of greenness were produced by the GAPI, AES, and AGREE tools. Results from the Red-Green-Blue 12 (RGB 12) algorithm for whiteness and BAGI for blueness indicate that the method is very practical, cost-effective, and environmentally friendly., Highlights: The results of this study could pave the way for more eco-friendly and effective AQbD methods to be used in the future for evaluating various sweeteners using green solvents., (© The Author(s) 2024. Published by Oxford University Press on behalf of AOAC INTERNATIONAL. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

In the present study, a selective electrochemical technique to determine Zineb fungicide based on molecularly imprinted polymer (MIP) as a simple and fast method was developed. The MIP was synthesized on a glassy carbon electrode (GCE) modified with single walled carbon nanotube (SWCNT) through electropolymerization of ortho-aminophenol (o-AP) monomer and Zineb fungicide analyte. Some ions and compounds were examined as the interfering species to investigate the selectivity of the developed sensor. This research proposes simple determination of Zineb fungicide with a linear range 5–1000 fM and limit of detection (LOD) 1.6 fM. Finally, this strategy was successfully used to detect Zineb in some vegetable and fruit samples such as cucumber, potato, tomato, lettuce, peach, and apple with a satisfactory recovery range between 98.85 and 102.00%. The obtained results indicated that the newly developed method is stable, convenient, and has easy preparation steps with low-cost materials. It can be used for rapid diagnosis of Zineb in crops and agriculture products, which holds great promise in detection of environmental pollutants. • The detection of Zineb fungicide using MIP was reported for the first time. • The MIP was synthesized by electropolymerization on the GCE modified with SWCNT. • MIP/SWCNT/GCE provided a good linear range and low LOD towards Zineb. • The modified electrode was successfully applied in food samples. • Sensor performs well in selectivity, stability, repeatability, and reproducibility. [ABSTRACT FROM AUTHOR]

[Display omitted] • A dual-response fluorescent probe RPT for detecting SO 2 and HClO is synthesized. • The fluorescent probe can monitor SO 2 and HClO with a wavelength difference of 85 nm. • The fluorescent probe has simple synthetic method and is easy to be obtained. • Fluorescent probe can image SO 2 and HClO in living cells (HeLa and RAW 264.7 cells). • Fluorescent probe can detect SO 2 and HClO in various water and food samples. Hypochlorous acid (HClO) and sulfur dioxide (SO 2) play vital roles in various fields, including living organisms, water samples, food and so on. High doses of SO 2 and HClO are seriously harmful to human and are associated with a variety of diseases. Therefore, monitoring the level of SO 2 and HClO in various fields is significant for exploring their roles. In this work, a novel dual-response fluorescent probe RPT for detecting SO 2 and HClO is successfully designed and synthesized, which is composed by pyrylium moiety and thiazine part. The fluorescent probe RPT can respectively monitor SO 2 and HClO by two well-separated emission wavelength with an obvious difference of 85 nm. The fluorescent probe RPT also displays desired properties such as simple synthetic method, high sensitivity and selectivity. In addition, as a biocompatible molecule, RPT has been successfully used for monitoring SO 2 and HClO in HeLa cells and RAW 264.7 cells in two different channels (red channel and green channel). More importantly, SO 2 and HClO levels in various water and food samples have been detected with satisfactory results. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple and fast-responsive fluorescent chemosensor BTP was developed for S2-. • BTP featured high sensitivity and specificity for S2- via fluorescent color change. • BTP was applied to real water, test strips, and food systems to detect S2-. • BTP is first applied to trace food spoilage among benzothiazole-based S2- probes. • Detecting mechanism of S2- by BTP was demonstrated to be deprotonation of phenol. The detection of S2− is required because of its harmful effects on human health. This led us to strategically design a new benzothiazole-based fluorescent chemosensor BTP (2-(benzo[d]thiazol-2-yl)-4,6-dichlorophenol). This sensor undergoes a fluorescence color change from orange to green in the presence of S2− via the deprotonation of phenol in near-perfect water. The detection limit for S2− reached 0.78 μM and BTP could selectively probe S2− over other competing analytes. The process whereby BTP responds to S2− was suggested to be improved intramolecular charge transfer (ICT), as was demonstrated by extensive DFT calculations. Particularly, BTP was successfully applied to detect S2− in zebrafish, real water, and beverage samples. Further, test strips coated with BTP were used to monitor the S2− released in raw meat. BTP is the first benzothiazole-based chemosensor developed to detect the S2− released from various types of food samples. The proposed method offers a novel tool for measuring S2− in biological and environmental systems, as well as the food quality under on-site conditions. [ABSTRACT FROM AUTHOR]

A comprehensive overview of bisphenol endocrine disruptors in food and the related sample pretreatment techniques and analytical methods for food analysis were presented. [Display omitted] • Bisphenols have wide applications in our life. • Bisphenols have chronic and acute toxicity for organisms and humans, such as endocrine disruption, estrogen syndrome, carcinogenicity and so on. • This article summarizes and discusses the physicochemical properties, applications and hazards of bisphenols. • Efficient pretreatment and analytical methods used for detecting bisphenols in various foods are emphasized. • This article predicted the challenges and research directions for bisphenols in the future. Bisphenols (BPs) are organic compounds commonly found in resins and plastics used for food packaging, tableware, bottle tops, water pipes, and epoxy coatings in metal cans. BPs can migrate from these materials into food, leading to human exposure and bioaccumulation. Many BPs have been found to have endocrine-disrupting and other toxic effects, causing adverse health effects and raising concerns about food safety worldwide. Sensitive and accurate detection of BPs can effectively avoid their hazards, which is one of important measures to improve food safety. However, food sources are wide, food matrices are complex, the structures of BPs are diverse, and their content are very low. It is necessary to remove most matrices and interfering substances to enrich BPs from food samples. At the same time, rapid, sensitive and efficient detection of BPs is also very important for food safety. Therefore, sample pretreatment techniques and detection methods play crucial roles in monitoring bisphenol endocrine disruptors in foods. This article discusses sample pretreatment techniques and analytical assays used for bisphenol endocrine disruptors in foods. The aim is to provide research ideas for the development of new techniques and methods. The article summarises and discusses the physicochemical properties, applications, and hazards of BPs. Furthermore, this text predicts future challenges and research directions for BPs. These include internal exposure levels and health effects, toxicity mechanisms, novel sensors, and eco-friendly food packaging materials. [ABSTRACT FROM AUTHOR]

Cys plays significant roles in food industries. It is very necessary to on-site quantify Cys content in food samples. Herein, we rationally developed a fluorescent sensor, YF , for on-site measurement of Cys in various foodstuffs. Sensor YF showed fluorescence response to Cys in near infrared (NIR) region, which could dramatically mitigate the interference of autofluorescence in foodstuffs. Moreover, sensor YF exhibited obvious colorimetric change to Cys. Accordingly, the sensor YF was capable of detecting Cys via both fluorescence method and colorimetric method, making the detection more reliable. Sensor YF also presented high selectivity and sensitivity to Cys, and its detection limits was measured to be 88 nM. The practical application demonstrated that sensor YF was able to monitor Cys in live cells and zebrafish via fluorescence imaging. Moreover, variations of Cys concentration in spinach leaves under different Cd2+ stress were effectively tracked. To accomplish on-site quantitation of Cys content in foodstuffs, a simple and portable measuring device was made. Sensor YF and the portable measuring device were successfully utilized for quantitation of Cys in food samples such as dry red pepper, tomato and soy bean. The detection method established herein will be conveniently employed for on-site quantitation of Cys in various food samples. [Display omitted] • A novel fluorescent sensor for detecting Cys via both NIR fluorescence method and colorimetric method has been developed. • To accomplish on-site quantitation of Cys level in food samples, a simple and portable measuring device was made up. • The sensor and portable measuring device were firstly applied for on-site quantitation of Cys in various food samples. [ABSTRACT FROM AUTHOR]

90Sr and 210Pb are considered to be key radionuclides in internal exposure resulting from dietary intake, however, the established methods employed for their detection are time-comsuming. A method for the sequential separation of 90Sr and 210Pb using a Sr·spec resin by LSC measurement is developed, which is highly suitable for food safety monitoring as its minimal sample requirements. The sequential separation of Sr and Pb from the sample was using 0.05 mol/L HNO 3 and 0.05 mol/L C 6 H 5 O 7 (NH 4) 3. The chemical recoveries of Sr and Pb measured using ICP-OES were 72–83% and 80–88%, respectively. The minimum detectable activities of 90Sr and 210Pb in the food sample were 36.2 mBq/kg and 28.6 mBq/kg, respectively, obtained from a 0.1 kg fresh sample and 300 min counting time. The method was validated using reference materials and compared with other methods. The feasibility of the developed method for other highly complex food matrices needs further investigation. • Sequential separation of 90Sr and 210Pb in food samples using Sr.spec resin, measured by LSC. • The chemical recoveries of Sr and Pb were 72–83% and 80–88%, respectively. • The MDA of 90Sr and 210Pb were 36.2 mBq/kg and 28.6 mBq/kg, respectively. • The method was validated by reference materials and compared to other methods. [ABSTRACT FROM AUTHOR]

Sulfite, widely used in food and pharmaceutical industries, poses significant health and safety concerns, necessitating efficient detection methods. This study introduces three novel red fluorescent probes (MCC-BT, MCC-TI, and MCC-DM), synthesized by integrating chromene derivatives with various electron-withdrawing groups. These probes effectively detect sulfite in both food samples and living cells, leveraging a mechanism transition from intramolecular charge transfer (ICT) to photo-induced electron transfer (PET). They demonstrate low detection limits (2.0 μM, 0.42 μM, and 0.34 μM, respectively) and offer advantages including large Stokes shifts, minimal interference, and colorimetric capabilities. We also developed smartphone-compatible test paper strips for convenient sulfite detection in real-world samples. The probes' effectiveness is further evidenced through sulfite quantification in Traditional Chinese Medicine ingredients. Additionally, their robust fluorescent imaging potential for cellular sulfite sensing highlights their significant contribution to analytical chemistry and biomedical research. • Three probes exhibit red fluorescence with exceptional sensitivity, outstanding selectivity, and large Stokes shifts. • Portable detection of sulfite in real samples is achieved using a smartphone. • Quantification of sulfite levels is performed in Traditional Chinese Medicine ingredients samples. • These probes can be employed for real-time monitoring of sulfite in living cells. [ABSTRACT FROM AUTHOR]

As a group of the most notorious carcinogens, N- nitrosamines (NAs) are highly toxic and usually involved in healthy issue of human daily life. An electrochemical sensor for N-nitrosodiphenylamine ( NDPhA ) detection was constructed based on graphene electrode material. The graphene was facilely obtained by direct reduction of graphene oxide (GO) with hydrazine hydrate, and further coated on the surface of the glassy carbon electrode (GCE) to fabricate the electrochemical sensor for NDPhA analysis in food samples. The present sensor showed excellent sensitivity and selectivity for the electrochemical determination of NDPhA under a reduction manner with the detection limit of 0. 6 μmol / L. It was also successfully used in beer and ham food samples with satisfactory recovery results. [ABSTRACT FROM AUTHOR]

Vitamin B3 (Nicotinamide) is involved in many vital reactions in the human body as the precursor of NAD and NADP. NAM deficiency can lead to pellagra thus foods are fortified with this vitamin. On the other hand, high intakes of NAM can cause some symptoms. Hence, a cheap, rapid, selective and sensitive determination of NAM concentration in foods is crucial. The present study propose a NAM analysis method for beef and wheat flour by employing a molecularly imprinted polymer based solid phase extraction clean-up coupled with HPLC-UV. Precipitating polymerization technique for fabrication of NAM molecularly imprinted microspheres was utilized. The effects of polymer ingredients including functional monomer, cross-linker monomers, template and solvent were investigated on binding characteristics. The binding behavior of the polymer well modeled through Freundlich equation and the polymer showed high selectivity of NAM over nicotinic acid (NA). In a kinetic study, 79% of NAM binding and 96.5% of NAM release occurred immediately. The NAM imprinted microspheres were packed into SPE for NAM extraction, food samples injected and the output analyzed with HPLC-UV. Good linearity was obtained for solid phase extraction of NAM in the range 148–5000 μg L-1 (R² = 0.999) and high extraction recoveries of 77–102% and 81–87% were obtained for NAM in beef and wheat flour samples, respectively. The limit of detection (LOD) and limit of quantification (LOQ) for nicotinamide were 44 μg L-1 and 148 μg L-1, respectively. The overall inter-day and intra-day relative standard deviations of 2.13% to 5.31% for wheat flour (n=4), and 1.89% to 5.22% for beef samples were obtained, demonstrating good precision of the proposed method in its application for real sample analysis. [ABSTRACT FROM AUTHOR]

High levels of dioxins and dioxin-like compounds in the food and their adverse effects on human health are of increasing concern. Since milk is one of the most essential human nutritional resources, the present study aims at determining dioxins and PCBs in raw milk samples from four farms in North of Iran and raw and pasteurized samples from three farms and five dairy factories in Vicinity of Tehran (capital of Iran). Total toxic equivalence (TEQ) of dioxin and PCBs have been determined, using the DR-CALUX® bioassay. Results reveal that all samples are contaminated with dioxins and PCBs, comparatively. The total dioxins and PCBs levels in raw milk samples from the north range from 4.08 to 0.97 pg/gfat and for the raw samples and pasteurized samples from Tehran Province from 1.89 to 0.63 pg/gfat and 0.1 to 0.03 pg/gfat, respectively. The mean concentration of dioxins/PCBs is higher in samples from the north of Iran. This may be because of the common method of removing domestic and agricultural disposal in this area. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Vanillin (VA) is a common additive used in cakes and beverages. Excessive addition of VA can cause a number of health problems. Therefore, the rapid detection of VA in food samples is well worth investigating. In this work, ZnS fibers were synthesized via simple chemical vapor deposition. The as-prepared ZnS fibers (ZnSF) were then used as substrate for PdZn nanopartciles loading. The prepared composite was characterized using SEM, XRD and EDX. The the ZnSF-PdZn composite was then used for fabrication of VA electrochemical sensor. The prepared electrochemical sensor showed an excellent sensing performance towards VA oxidation. Under the optimized condition, the ZnSF-PdZn modified glassy carbon electrode could linearly detect VA between 0.05 and 150 µM with a low detection limit of 20 nM. The proposed electrochemical sensor also been applied for VA sensing in custard, milk tea and cake. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of gold nanoclusters (AuNCs-CCY) using peptides as templates. • The fluorescence of R6G was quenched by gold nanocluster (AuNCs-CCY). • Once introduced, Pb2+ triggered the reversion of quenched fluorescence. • Sensitive and selective detection of Pb2+ is achieved by regulating the FRET effect. • This detection method simplifies operational procedures, achieve rapid detection, and reduces associated costs. Lead pollution has remained a significant global concern for several decades due to its detrimental effects on the brain, heart, kidneys, lungs, and immune system across all age groups. Addressing the demand for detecting trace amounts of lead in food samples, we have developed a novel biosensor based on fluorescence resonance energy transfer (FRET) from fluorescein R6G to gold nanoclusters (AuNCs-CCY). By utilizing polypeptides as a template, we successfully synthesized AuNCs-CCY with an excitation spectrum that overlaps with the emission spectrum of R6G. Exploiting the fact that Pb2+ induces the aggregation of gold nanoclusters, leading to the separation of R6G from AuNCs-CCY and subsequent fluorescence recovery, we achieved the quantitative detection of Pb2+. Within the concentration range of 0.002–0.20 μM, a linear relationship was observed between the fluorescence enhancement value (F-F 0) and Pb2+ concentration, characterized by the linear equation y = 2398.69x + 87.87 (R2 = 0.996). The limit of detection (LOD) for Pb2+ was determined to be 0.00079 μM (3σ/K). The recovery rate ranged from 96 % to 104 %, with a relative standard deviation (RSD) below 10 %. These findings demonstrate the potential application value of our biosensor, which offers a promising approach to address the urgent need for sensitive detection of heavy metal ions, specifically Pb2+, in food samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new near-infrared fluorescent probe HR for specially responses toward H 2 S was synthesized. • Probe displays a colormetric and NIR fluorescent response toward H 2 S with large Stokes shift, high selectivity and sensitivity. • Probe can be applied for sensing detection of H 2 S in food spoilage and living cells. Hydrogen sulfide (H 2 S), as a biomarker signaling gas, is not only susceptible to food spoilage, but also plays a key function in many biological processes. In this work, an activated near infrared (NIR) H 2 S fluorescent probe was designed and synthesized with quinoline-conjugated Rhodols dye as fluorophore skeleton and a dinitrophenyl group as the responsive moiety. Due to the quenching effect of dinitrophenyl group and the closed-loop structure of Rhodols fluorophore, probe itself has a very weak absorption and fluorescence background signal. After the H 2 S-induced thiolysis reaction, the probe exhibits a remarkable colormetric change and NIR fluorescent enhancement response at 716 nm with large Stokes shift (116 nm), and possesses high sensing selectivity and sensitivity with a low detection limits of 330 nM. The response mechanism is systematically characterized by 1H NMR, MS and DFT calculations. The colorimetric change allows the probe to be used as a test strips to detect H 2 S in food spoilage, while NIR fluorescent response helps the probe monitor intracellular H 2 S. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple method for simultaneous recognition of d / l -Carn was investigated. • d / l -Carn were mobility separated by their ternary diastereomeric complex by adding Nat and meal ions. • Metal ions in group IA (Li+, Na+, K+, Rb+, Cs+) have separation effects. • Theoretical calculations were performed to elucidate the enantiomeric separation at the molecular level. • The proposed method was applied to l / d -Carn detection in beverage samples and fresh pork. This work presents a straightforward approach to the separation d / l -carnitine (d / l -Carn) using ion mobility–mass spectrometry (IM-MS) and theoretical calculations. Natamycin (Nat) was used as separation reagent to interact with the Carn, metal ions (G) were employed as ligand, the resultant ternary complexes [ d / l -Carn + Nat + G]+ were observed experimentally. IM-MS results revealed that d / l -Carn could be baseline separated via complex formation using Li+, Na+, K+, Rb+, and Cs+, with a maximum peak separation resolution (R p-p) of 2.91; Theoretical calculations were performed to determine the optimal conformations of [ d / l -Carn + Nat + Li/K]+, and the predicted collisional cross section values were consistent with the experimental values. Conformational analysis was used to elucidate the enantiomeric separation of d / l -Carn at the molecular level via the formation of ternary complexes. Furthermore, quantitative analyses for the determination of the enantiomers were established with effective linearity and acceptable sensitivity. Finally, the proposed method was successfully applied in the determination of d / l -Carn in food samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • The quercetin was detected using the electrochemical sensing method. • The PrV@g-CN composite was prepared by the hydrothermal method. • The synergetic effect between the PrVO 4 and g-CN enhanced the detection of Qc. • The PrV@g-CN shows a linear range of 0.05–252.0 µM and LOD 0.002 µM of towards Qc. • The proposed sensor was applied for Qc detection in green and black tea samples. Flavonoids or phenolic compounds are part of the daily intake of every human being. Though they are positive traders for metabolism, excessive intakes bring about detrimental impacts on human health. Herein, the anti-cancer capacitive nature quercetin (Qc) was electrochemically detected through the rare earth metal-based sphere like praseodymium vanadate (PrVO 4) entrapped graphitic carbon nitride (g-CN) as electrode modifiers. The nanocomposite was prepared by the one-pot hydrothermal method and characterized by phase compositional and morphology-based techniques. The existing synergistic nature between the PrV@g-CN (praseodymium vanadate@graphitic carbon nitride) makes them have an enhanced electrochemical response towards the Qc than the individual material. The obtained cyclic voltammogram and differential pulse voltammogram profile show one major oxidation peak which is attributed to the conversion of quercetin to quercetin-o-quinone. The PrV@g-CN/GCE (GCE- glassy carbon electrode) shows a good electrochemical active surface area (A = 110 cm2) and linear range between 0.05 and 252.00 μM with a LOD (limit of detection) of 0.002 µM. Moreover, the PrV@g-CN/GCE exhibits good current retention (94.76 %) around 14 days and appreciable repeatability (RSD- 0.5 %) and reproducibility (RSD- 1.3 %) towards the Qc. The real-time implementation of the proposed sensor exhibits a good recovery range towards the black tea (95.00–98.10 %) and green tea (97.80–99.60 %). [ABSTRACT FROM AUTHOR]

Unmodified hairy basil seed mucilage (Ocimum basilicum L.), with attractive features as structural functionality and adsorption capacity, was employed as a green biosorbent for dispersive solid phase extraction and enrichment of oxytetracycline, tetracycline, and doxycycline before quantitation by HPLC-UV for the first time. Hairy basil crushed seed increased the contacting surface area and was completely dispersed in the sample solution to extract tetracyclines under acidic condition with the assistance of ultrasonic waves. The analytes in the extraction phase were separated on a C 18 column under isocratic condition with a mobile phase consisted of acetonitrile and trifluoroacetic acid. Influence of chemical and physical variables on the extraction efficiency of the developed method was investigated and optimized systematically. Under the optimal condition of all experimental parameters, good linear ranges were obtained at 15.0–500 μg L−1 for tetracyclines with determination coefficients more than 0.9994. Limits of detection (LODs) and limits of quantitation (LOQs) ranged 5.0–7.0 and 15.0 μg L−1, respectively. Relative standard deviations (RSDs) of the proposed method at 100 and 300 μg L−1 for TCs were less than 13 % and 10 %, respectively with percentage TC recoveries from spiked standard ranging 83.1–109.9 %. This simple, reliable, cost-effective, and environmentally friendly method was successfully applied for the analysis of tetracycline residues in milk. The greenness of the proposed method was assessed using the Analytical Eco-Scale and AGREE protocol. [Display omitted] • Unmodified HBSM was used as a green biosorbent for DSPE for the first time. • Alternative DSPE based on biosorbent was utilized to enrich TC residues in milk. • UAE was synergized with DSPE to enhance extraction efficiency. • After preconcentration using the developed method TCs were quantified by HPLC-UV. • This method is simple, reliable, cost-effective, and environmentally friendly. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, we used voltammetric method in order to examine the electrochemical behavior of BPA. Hence, we constructed a new electrochemical sensor to detect BPA on the basis of the modified carbon paste electrode using FeNi3/CuS/BiOCl as a novel nanocomposite. Results showed that when using optimized conditions, the new BPA sensor has a wide linear range between 0.1 μM and 300 μM, lower limit of detection of 0.05 μM, and good reproducibility and stability. Based on the findings, it could be concluded that our sensor can be substantially utilized for detecting BPA in the food samples with reasonable outputs. [ABSTRACT FROM AUTHOR]

In this project, we performed an electrochemical investigation using a reduced graphene (rG) decorated CdO nanocomposite/1-methyl-3-octylimidazolium tetrafluoroborate ionic liquid (MOITF) carbon paste electrode (rG-CdO/MOITF/CPE) for determination of ferulic acid in food samples. In preparation of rG-CdO/MOITF/CPE, 6% w/w rG-CdO nanocomposite and 20% v/v room temperature ionic liquid were used to modify the bare CPE. SEM (Scanning Electron Microscopy) and XRD (X-Ray Diffraction) methods were applied to characterize the structure of the synthesized rG-CdO nanocomposite. At all the stages of this research, phosphate buffer solution (PBS) with the pH of 5.0, as an optimized pH condition, was used. The electron transfer coefficient (α) was obtained ⁓0.68 by recorded data from cyclic voltammogram of rG-CdO/MOITF/CPE in the presence of ferulic acid. In addition, using the chronoamperometric technique, the diffusion coefficient (D) of ferulic acid at rG-CdO/MOITF/CPE was calculated 5.4 × 10−5 cm2/s. Using the square wave voltammetry method, the linear dynamic range (LDR) was calculated to be from 0.02 to 400 μM, and the limitation of detection (LOD) was obtained as 8.0 nM. Eventually, the rG-CdO/MOITF/CPE was utilized to determine the amount of ferulic acid in food samples, and statistical calculations confirmed the sensitivity, selectivity, and precision of rG-CdO/MOITF/CPE, which is an electroanalytical tool. [ABSTRACT FROM AUTHOR]

Rhodamine B hydrazide and 2‐chloroquinoline‐3‐carbaldehyde derivatives were used to synthesize novel colorimetric sensors for highly selective detection of copper ion. The measurement was based on the interaction between the synthesized ligands and Cu2+ and the sharp color change of the ligand from yellow to pink in the presence of Cu2+. Increase in absorbance intensity at the new appeared absorbance peak was used as an analytical signal. The effect of parameters, such as time and sensor concentration were also investigated and discussed. The calibration curve was considered too under the optimum experimental conditions and was linear in the range 0.05–5.00 μg mL−1 with a limit of detection 0.016 μg mL−1. The interferences of some common ions were studied and the synthetic ligand was found to be a high selective sensor. Selectivity of the proposed method makes it as an applicable technique for the determination of copper in foodstuff samples. [ABSTRACT FROM AUTHOR]

With the merits of non-destructive, high penetration ability and minimizing autofluorescence, near-infrared (NIR) fluorescent probes have attracted much attention. In this paper, a NIR emission fluorescent turn-on probe THQ-L for H 2 S was synthesized by the knoevenagel condensation between tetrahydroquinoxaline-6- formaldehyde derivative and 2-benzothiazoleacetonitrile. THQ-L can recognize H 2 S through tandem reaction triggered by HS− to construct 1,4-diethylpiperazine-modified iminocoumarin-benzothiazole, which produces a strong red fluorescent signal. THQ-L displayed an excellent selectivity toward H 2 S, a large stokes shift (126 nm), a high signal-to-noise ratio (200-fold), the detection limits of 38.3 nM in PBS (10 mM, pH 7.4, 30% THF). The application study indicates that THQ-L can sensitively detect H 2 S in red wine, natural waters, living cells and can be prepared for a test paper strip for the qualitative detection of H 2 S. Image 1 • A novel NIR fluorescent probe for H 2 S based on tandem reaction to construct iminocoumarin-benzothiazole. • TCF-DNs detects H 2 S with a large Stokes shift, a high signal-to-noise ratio, a low detection limit. • TCF-DNs can detect H 2 S in red wine, natural waters, and image H 2 S living cells. • TCF-DNs was prepared for test strip and was used for the qualitative detection of H 2 S. [ABSTRACT FROM AUTHOR]

An efficient magnetic mesoporous structure was designed and prepared for the facile pre-concentration of As(III) ions. To prepare the sorbent, core–shell magnetic silica nanoparticles were covered by MCM-41 like structure and then the surface was modified by guanidine via an amine linker (GA-MSMP). The prepared adsorbent was investigated as an effective and sensitive material for the adsorption of arsenic ions from the aqueous solution by applying a normal batch method. The imperative variables of the adsorption were studied to increase efficiency. The dynamic and static processes were tested that matched a pseudo-second-order of kinetic model and the Langmuir isotherm model, respectively. The sorbent reusability was investigated and it was confirmed that the designed product could be applied at best for six cycles successively without any significant efficiency losing. The synthesized product was tested to determine and pre-concentrate trace amounts of arsenic ions in rice and natural waters as a real sample. A desorption process applying 5 mL of hydrochloric acid (0.5 mol L−1) as an eluent, exhibited about 98% recovery of the As(III) ions adsorbed on the GA-MSMP sorbent. The maximum adsorption capacity of the GA-MSMP was calculated to be 312 mg g−1 for adsorption of As(III) under the optimal conditions. [ABSTRACT FROM AUTHOR]

Escherichia coli serotype O157: H7 and Shigella dysenteriae type 1 as the Shiga toxin‐producing bacteria cause some acute gastrointestinal and extraintestinal diseases such as hemorrhagic uremic syndrome and bloody diarrhea in human. Stx genes are the key virulence factors in these pathogens. The aim of this study was to develop HRMA assay to differentiate stx1A gene for detection of E. coli serotype O157: H7 and Sh. dysenteriae type 1 and determine the prevalence of these pathogens in food samples using this method. PCR‐HRMA assay and gold standard methods have been carried out for identification of pathogens among 135 different food samples. We found HRMA method a sensitive and specific assay (100 and 100%, respectively) for differentiation of stx1A gene, consequently, detection of these pathogens in food samples. Also, the highest prevalence of E. coli serotype O157: H7 and Sh. dysenteriae type 1 harboring stx1A gene was observed in raw milk and vegetable salad samples, respectively. HRMA as a rapid, inexpensive, sensitive and specific method is suggested to be used for differentiation of stx1A gene to detect E. coli serotype O157: H7 and Sh. dysenteriae type 1 as the key pathogens for safety evaluation of food samples. [ABSTRACT FROM AUTHOR]

H 2 S has attracted significant attention as an important gasotransmitter or gasomediator due to its essential roles in many pathological and physiological processes in living systems, and due its being one of the compounds involved in food production and spoilage. The real-time detection/visualization of H 2 S levels in practical samples is of great significance for environmental monitoring, food engineering, and biological analysis. In this study, for the first time, a symmetric pyrylium HN9 dye was designed and synthesized. The new HN9 dye possessed near-infrared emission at 688 nm, a large Stokes shift of 83 nm, and good brightness for high fidelity and low excitation interference testing. Thus, the HN9 dye was employed to prepare a representative HN9DNP probe for the detection H 2 S. By regulating a photoinduced electron transfer mechanism, the H 2 S probe exhibited a 24-fold fluorescence enhancement, a linear detection range of 0–30 μM, and a good detection limit of 0.48 μM. Moreover, the HN9DNP probe was successfully applied for sensing H 2 S in environmental water samples, cell lysates, food samples, and living cells, which provided an efficient approach for the highly sensitive and selective detection of H 2 S in practical applications. [Display omitted] • HN9 could emit NIR fluorescence of 688 nm with large Stokes shift. • HN9DNP showed 24-fold fluorescence enhancement to H 2 S. • HN9DNP was applied for sensing H 2 S in water samples and cell lysates. • HN9DNP based test strips could sense H 2 S release during food spoilage. • HN9DNP was applied for imaging H 2 S in living cells. [ABSTRACT FROM AUTHOR]

• A highly selective fluorescent probe TPE-O for HSO 3 − detection has been developed. • TPE-O showed ultrafast fluorescence and colorimetric dual response to HSO 3 −. • TPE-O can detect the content of HSO 3 −in sugar and wine samples. • TPE-O can be loaded on agarose hydrogel to detect SO 2 gas. SO 2 is one of the main components of air pollution gas, its derivatives HSO 3 − and SO 3 2− were considerable used as food additive because of their antiseptic and bacteriostatic effects. Excessive intake of HSO 3 − is harmful to human health, so it is extremely important to detect the content of HSO 3 − in food sample by effective method. In this work, a small molecular fluorescence probe TPE-O based on tetraphenylethene fluorophore was designed and synthesized. The probe showed ultrafast (< 3 s) and obvious colorimetric response to HSO 3 − with high selectivity and sensitivity (LOD = 210 nM). The possible Michael-type addition of HSO 3 − on the activated C = C bond blocked the π-conjugated system, thus lead to changes in fluorescence and absorption spectra. Probe TPE-O not only can detect the content of HSO 3 − in sugar and wine, but also can be loaded on agarose hydrogel to detect SO 2 gas. Therefore, this work provided a powerful tool for the detection of HSO 3 − in food samples and SO 2 gas. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)