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Chloramphenicol is a widely used bactericide and highly effective antibiotic in aquaculture and livestock breeding. To protect human health, detecting chloramphenicol residues in animal-derived food products has become increasingly important. This review introduces the properties of chloramphenicol, the limit standards, and the hazards of residual chloramphenicol in animal-derived food products. Furthermore, it describes commonly used chloramphenicol detection methods. In addition, the review thoroughly analyzes and summarizes the advantages and disadvantages of different detection methods, outlining methods to improve the efficiency and precision of chloramphenicol detection to ensure the quality and safety of animal-derived food products. Finally, the prospects for developing advanced detection techniques and analytical methods are prospected.

Herein, polyvinylpyrrolidone-stabilized Au nanorods were controllably implanted into ZIF-8 to form a well-uniformed AuNRs@ZIF-8 electrocatalyst with a multicore-shell structure. After characterizing the chemical and physical properties, a novel electrochemical sensing platform was fabricated for 2-chlorophenol (2-CP) monitoring based on the AuNRs@ZIF-8 modified glassy carbon electrode. Due to the unique electrochemical property of AuNRs cores and ultra-porous architecture of ZIF-8 shell, the electrocatalyst would effectively accelerate the electron transfer and greatly improve the electrochemical response of 2-CP. Under the optimized experimental conditions, the oxidation peak current of 2-CP enhanced linearly with the increase of its concentration between 0.010 and 40 lM, and the limit of detection was 3.6 nM based on S/N = 3. Meanwhile, the prepared AuNRs@ZIF-8 electrode showed favorable stability, reproducibility, and selectivity, which could be applied to the accurate analysis of 2-CP in aquaculture with standard addition recovery ranging from 96.67% to 104.0%. Key words: Au nanorods, ZIF-8, core-shell structure, 2-chlorophenol, electrochemical determination. Dans le cadre des présents travaux, nous avons implanté de façon contrôlable des nanobâtonnets d'or (NB-Au) stabilisés par la poly(vinylpyrrolidone) dans un réseau d'imidazolate zéolitique (ZIF-8 pour zeolitic imidazolate framework-8) pour former un électrocatalyseur uniforme de type NB-Au@ZIF-8 présentant une structure multi-coeurs--coquille. Après caractérisation des propriétés chimiques et physiques, nous avons réalisé un nouveau système de détection électrochimique pour le dosage du 2-chlorophénol (2-CP) reposant sur une électrode de carbone vitreux modifiée par le composite NB-Au@ZIF-8. Grâce aux pro-priétés électrochimiques uniques des coeurs formés par les NB-Au et l'architecture ultraporeuse de la coquille de ZIF-8, l'électrocatalyseur accélérerait efficacement le transfert d'électrons et améliorerait grandement la réponse électrochimique du 2-CP. Dans les conditions expérimentales optimisées, l'amplification du courant de crête de l'oxydation du 2-CP était pro-portionnelle à l'augmentation de la concentration de ce dernier dans le domaine de linéarité de 0,010 à 40 lM, la limite de détection étant de 3,6 nM si l'on considère un rapport signal/bruit de 3. Par ailleurs, l'électrode à base de NB-Au@ZIF-8 que nous avons pré-parée a montré une stabilité, une reproductibilité et une sélectivité favorables. Elle pourrait ainsi être appliquée au dosage précis du 2-CP en aquaculture, avec un taux de récupération par ajouts dosés allant de 96,67 % à 104,0 %. [Traduit par la Rédaction] Mots-clés : nanobâtonnets d'or, ZIF--8, structure coeur-coquille, 2-chlorophénol, dosage électrochimique., Introduction Chlorophenols are an important class of aquatic contaminants released to the environment mainly during the manufacturing of pesticides, herbicides, disinfection, glue, leather, paint, and wood preservation and are presentinaquatic [...]

The farming pattern of crayfish significantly impacts their quality, safety, and nutrition. Typically, green and ecologically friendly products command higher economic value and market competitiveness. Consequently, intensive farming methods are frequently employed in an attempt to replace these environmentally friendly products, leading to potential instances of commercial fraud. In this study, stable isotope and multi-element analysis were utilized in conjunction with multivariate modeling to differentiate between pond-intensive, paddy-ecologically, and free-range cultured crayfish. The four stable isotope ratios of carbon, nitrogen, hydrogen, and oxygen (δ13C, δ15N, δ2H, δ18O) and 20 elements from 88 crayfish samples and their feeds were determined for variance analysis and correlation analysis. To identify and differentiate three different farming pattern crayfish, unsupervised methods such as hierarchical cluster analysis (HCA) and principal component analysis (PCA) were used, as well as supervised multivariate modeling, specifically partial least squares discriminant analysis (PLS-DA). The HCA and PCA exhibited limited effectiveness in classifying the farming pattern of crayfish, whereas the PLS-DA demonstrated a more robust performance with a predictive accuracy of 90.8%. Additionally, variables such as δ13C, δ15N, δ2H, Mn, and Co exhibited relatively higher contributions in the PLS-DA model, with a variable influence on projection (VIP) greater than 1. This study is the first attempt to use stable isotope and multi-element analysis to distinguish crayfish under three farming patterns. It holds promising potential as an effective strategy for crayfish authentication. [ABSTRACT FROM AUTHOR]

In view of the core–shell nanocomposites can complement the functions of the core and shell components, we here demonstrate a facile self-template strategy for synthesizing a one-dimensional rod-like hierarchical ZnO@ZIF-8 core–shell structure composed of a stabilized core and an active shell. The ZnO nanorods not only served as the template, but also as source of Zn ions for the in situ formation of zeolitic imidazolate framework-8 (ZIF-8) crystal shell, and the well-stabilized ZnO core preserved its own nature during the growth of the ZIF-8 shell. Furthermore, a sensing platform using ZnO@ZIF-8 as electrocatalyst was developed, which demonstrated salient electrocatalytic activity for diethylstilbestrol (DES) oxidation. The concentration of DES was directly proportional to its anodic peak current in the range of 2 nmol/L to 2 µmol/L, and ultralow detection limit of 0.73 nmol/L (S/N = 3) was achieved. The proposed method also gave excellent selectivity, reproducibility, and stability, showing promising analytical performance for the measurement of DES in food samples of animal origin. [ABSTRACT FROM AUTHOR]

Highly stable and photoluminescent methylammonium lead halide perovskite quantum dots (MAPbBr3 PQDs) have been synthesized and applied for the fluorescence quenching detection of clothianidin in fruit and vegetable samples. Characterizations using different techniques, including photoluminescence (PL), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and time-resolved PL (TRPL), show that static quenching is the dominant fluorescence quenching mechanism of MAPbBr3 PQDs with clothianidin. Hydrogen bonds or van der Waals forces play major roles in the MAPbBr3 PQDs–clothianidin interaction. Under optimized conditions, the relative PL intensity of MAPbBr3 PQDs is linear to the concentration of clothianidin in the 0.0 and 20.0 mg/L range with a detection limit of 0.17 μg/kg. Excellent recoveries of 79.5–115.4% were acquired for radish and banana samples with a relative standard deviation below 9.4%. These results indicate that PQDs can be used for qualitative and quantitative identification of clothianidin, providing an effective detection method for risk prevention and control of neonicotinoid pesticide residues in agricultural products. [ABSTRACT FROM AUTHOR]

In the current study, an effective and simple procedure of extraction for the four benzophenone compounds from water samples was achieved by dispersive liquid–liquid microextraction (DLLME) based on the solidification of floating organic droplets (SFO) with a natural monoterpene enol as the extractant. As a natural, high solidification point, inexpensive, and environmentally friendly hydrophobic solvent, α−terpineol was selected firstly as an extractant for DLLME and could be collected and transferred easily after extraction by solidification at a lower temperature. Several main parameters closely related to extraction efficiencies, such as volume of extractant, extraction time, pH and salt concentration of the sample solution, temperature, and time of the solidification process, were investigated in detail. The results showed that the established method had good extraction performance for benzophenone compounds with enrichment factors in the range of 29–47. Furthermore, the linearities were over the range of 2–2000 µg/L, and the limits of detection were 0.12–0.53 µg/L for four benzophenone compounds. The recoveries ranged from 80.2% to 108.4%, with RSDs (intra- and inter-assay) less than 8.5%. At last, the method applicability was investigated by the determination of the benzophenone compounds in aqueous solutions, and satisfactory recoveries (83.0–107.0%) were acquired. Taken together, α−terpineol, a natural monoterpene enol, was first used as an extractant of DLLME-SFO, which provided an alternative method with simplicity and rapidity for the determination of benzophenone compounds in aqueous samples. [ABSTRACT FROM AUTHOR]