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In recent years, developing rapid, simple, and effective new methods to monitor food safety is standing out enough to be noticed. Electrospinning is an easy, versatile, and low-cost technique to fabricate multifunctional micro-and nanomaterials. The combination of electrospinning and biosensors is one of the most promising strategies and is expected to replace traditional detection materials. This paper reviews the research progress of electrospinning in food detection, including electrospinning materials generally used in the food field with their benefits of high aspect ratio, large specific surface area, tunable porosity, easy functionalization, easy handling, mechanical stability, such as natural polymers, synthetic polymers or the mixture of both. Besides, we also emphatically introduced the application of their intrinsic characteristics combined with biosensing platforms and list the sensitivity and detection limit of various methods and materials in detection, as well as their application potential, and the challenges faced by the on-site detection and the large-scale commercial applications in the food industry as future exploration headings, giving new thinking of nanomaterial applications for food safety detection. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3a and 3c are screened out from five D-A type dicyanoisophorone derivatives, which show high selectivity towards H 2 O 2. • 3a and 3c express colorimetric and fluorescent dual-signals towards H 2 O 2 with low detection limits (0.20 μM and 0.14 μM). • 3a and 3c are capable of H 2 O 2 detection in milk samples. • Low cytotoxicity allows 3a to be utilized as a H 2 O 2 fluorescence sensor in living HepG-2 cells and zebrafish. • A smartphone-based analysis method is utilized for the rapid quantitative detection of H 2 O 2 by 3c. Excessive residual hydrogen peroxide (H 2 O 2) disinfectant in food is harmful to human health. Therefore, it is necessary to develop efficient detection methods for H 2 O 2 detection. In this work, we designed and synthesized five D-A molecules 3a - 3e by introducing electron-donor substituents (–OCH 3 and –CH 3) to the electron-acceptor dicyanoisophorone skeleton in order to find out the suitable probes for H 2 O 2 detection. Among them, two promising probes, 3a and 3c , are screened out according to structure-property relationships. Based on the principle of intramolecular charge transfer (ICT), 3a and 3c express colorimetric and fluorescent dual-signals towards H 2 O 2 with low detection limits (0.20 μM and 0.14 μM) and rapid response (within 20 mins). The reaction mechanism between probes and H 2 O 2 is determined by 1H NMR and HRMS. Density functional theory (DFT) calculations are measured to study the regulation mechanism of structure adjustment on probs performance. Furthermore, a smartphone RGB analysis is utilized as a portable platform for the quantitative detection of H 2 O 2 without complicated instruments, indicating a high efficiency and on-site detection method for H 2 O 2. In addition, probes are applied to detect H 2 O 2 in milk samples, HepG-2 cells and zebrafish, suggesting the promising applications in food samples and physiological systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • L5 can achieve naked-eye recognition for I−. • The mechanism of subject-object recognition was elucidated. • The method can be used for I− detection in food. • L5 has lower detection limit and higher sensitivity. In this study, a cholesteric chiral artificial receptor L5 was synthesized and a rapid method for the detection of iodide ions was established. The addition of L5 to Ethanol/Tris (V/V = 1/1, pH 7.0) solution changed the iodide ion solution from colorless to light yellow to achieve the naked-eye identification. The identification pattern was confirmed with the help of spectral titration, job test and anti-interference test, and it was found that L5 bound to iodide ion in a 1:1 coordination ratio. It was also confirmed that the hydrogen atoms of the amide group of MeO-PhCONH in L5 and the hydrogen atoms of –COOCH 3 in L5 interacted with I− through hydrogen bonding force by 1H NMR titration, infrared spectroscopy, scanning electron microscopy and computer molecular simulation. The detection limit of L5 was 0.025 µmol/L, which could efficiently and conveniently detect iodide ions in food samples. [ABSTRACT FROM AUTHOR]

Formaldehyde (FA) is an environmental toxin and widely used in building and decorating materials, which is listed as a class 1 carcinogen. Silver ion (Ag+) has a beneficial bactericidal effect, while it can also cause silver poisoning and skin damage. Therefore, developing a quantitative detection technique for formaldehyde and Ag+ is necessary. In this study, a novel difunctional fluorescent probe (DBP) was designed and synthesized based on the natural product dehydroabietic acid, which could selectively detect formaldehyde and Ag+ through "turn-on" and "turn-off" fluorescence response, respectively. The probe DBP performed satisfactory nanomolar-level detection limit to formaldehyde (38 nM) and Ag+ (19 nM) in ethanol/PBS (3/7, v/v, pH = 7.4) solution. Furthermore, DBP could effectively recognize formaldehyde and Ag+ within a short response time (FA: 15 min, Ag+: 100 s) and a wide pH range (5–10). The sensing mechanisms of DBP to FA and Ag+ were well verified by 1H NMR titration, ESI-MS, DFT computation, and Job's plot analysis. What is more, the applications in bioimaging were carried out in MCF-7 cells and living zebrafish. Besides, the probe DBP was successfully applied in detecting FA and Ag+ in actual food and water samples, and the DBP -loaded filter paper was prepared for convenient tracking gaseous FA and Ag+. • A novel fluorescent probe DBP for detecting formaldehyde and Ag+ was synthesized. • DBP exhibits low LOD, short response time and wide pH range towards FA and Ag+. • DBP was utilized in food and water samples, filter paper test, and bioimaging. [ABSTRACT FROM AUTHOR]