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Veterinary drug residues in foods pose risks to consumers and promote antimicrobial resistance. Effective detection methods are needed to monitor and control residues. Recent advancements in analytical techniques for veterinary drug residue detection were reviewed. Key sample preparation methods, including QuEChERS, SPE, ASE, and LLE, were summarized. Instrumental analysis techniques including LC-MS/MS, GC-MS, immunoassays, CE and biosensors were examined. Recent trends and future directions were identified.LC-MS/MS and GC-MS provide the highest sensitivity and specificity for veterinary drug residue analysis. However, selectivity remains a challenge, particularly for complex matrices like meat and liver. Multi-residue methods now cover over 100 analytes, but analyzing new and legacy drugs lacking established methods is difficult. Increased sensitivity has been achieved through UHPLC and high resolution MS, but detection limits below 1 µg/kg often remain elusive. sSimplified onsite tests are gaining interest.More selective extraction strategies, data-driven multi-residue methods, microflow LC, and integrated analytical platforms may help address current challenges. Continued advances in sample preparation, instrumentation, data processing, and validation will be needed to fully realize the potential of veterinary drug residue detection and ensure food safety.

Background: Glucose detection is of great significance in biomedicine. In clinical medicine, diabetes seriously endangers human health. By accurately measuring the blood glucose content of diabetic patients, diabetes can be effectively monitored and treated. At present, there are many methods for measuring glucose content, such as chromatography, spectroscopy, and electrochemical methods. Among them, electrochemical glucose sensors are widely used because of their high reliability, low cost, and easy operation. Methods: Combining graphene with other nanomaterials (including graphene, metal oxides, semiconductor nanoparticles, polymers, dye molecules, ionic liquids and biomolecules) is an effective way to expand or enhance the sensing performance. Results: The composite of graphene and nanomaterials is an effective way to enhance the functionality of the electrochemical sensor. Graphene can accelerate electron transfer and realize direct electrochemistry and biological sensing. At the same time, graphene derivatives with rich composition and structure provide the possibility to further regulate their electrochemical performance. These graphene composite-based biosensors have shown excellent sensitivity and selectivity for glucose detection. Conclusion: Electrochemical glucose sensors based on graphene composite have received extensive attention. Although these materials have made significant progress in improving the sensitivity, lowering the detection limit and broadening the linear range, there are still facing challenges that require further study.

Rapid detection of tea polyphenol is necessary in food and beverages. In this work, we used cassava fibers as a substrate on which iron nanoparticles were immobilized. The proposed composite was used for surface modification of glassy carbon electrodes to prepare an electrochemical sensor for the detection of tea polyphenols. The SEM characterization results show that the iron nanoparticles on the surface of the cassava fibers were distributed uniformly. We investigated the electrochemical behavior of tea polyphenols on the surface of modified electrodes. The result indicated that the iron nanoparticles could facilitate the electron transfer rate and subsequently enhance the sensing performance. Meanwhile, we have optimized the detection parameters. The proposed sensor can linearly increase the peak current of tea polyphenol oxidation in the range of 3.5–31.5 µM with a equation of I (µA) = 0.01285c + 0.89734 (r = 0.9958). The detection limit can be calculated to be 0.1 µM. In addition, we have validated the proposed sensors in real samples. The results demonstrate that this sensor can be potentially used for the detection of tea polyphenols in beverages.

Bimetallic FeNi alloys embedding into biochar (FeNi-BC) catalysts with different Fe/Ni molar ratio were fabricated using rose petal as biomaterials. The as-fabricated FeNi-BC was employed to activate peroxydisulfate (PDS) toward tetracycline (TC) degradation. The effects of Fe/Ni atomic ratio on the structure feature of FeNi-BC and PDS activation efficiency were explored in detail. Results show that the optimum Fe0.8Ni0.2-BC prepared with Fe/Ni molar being 8:2 exhibited the best PDS activation efficiency toward TC degradation, with 97.01% of TC being removed in 15 min. Combining with the electron paramagnetic resonance (EPR), reactive oxygen species quenching, and electrochemical tests, the direct electron transfer (DET) and singlet oxygen accounted for TC degradation in the Fe0.8Ni0.2-BC activating PDS system. Because of that, the Fe0.8Ni0.2-BC had satisfactory resistance to inorganic anions and natural organic matters (NOMs). Based on the structure-activity relationship, it was found that more Fe0and pyrrolic N formation in FeNi alloys than single Fe or Ni embedding in BC facilitated in more PDS adsorption, thus more PDS* complex formation on the surface of catalysts to boost the TC degradation through DET mechanism. Moreover, Fe0.8Ni0.2-BC possessed trace Fe and Ni leaching, satisfactory stability, and easy recycling via magnetic separation. This study not only offers new insights for discriminating the catalytic active sites of biochar embedded bimetallic alloys catalysts activating PDS but also developed cost-effective and environment friendly catalysts for high-efficiently remove antibiotics via PS-AOPs.

In this study, to enhance the peroxymonosulfate (PMS)-assisted photocatalytic degradation of tetracycline (TC) under visible light over BiVO4, g-C3N4coupling and Na+doping was used to co-modify BiVO4to obtain g-C3N4/Na-BiVO4(CN/Na-BiVO4) heterojunction catalyst. The prepared CN/Na-BiVO4exhibited the apparently enhanced PMS-assisted photocatalytic TC degradation efficiency and can degrade approximately 98.20% of TC in 40 min, being 3.13 folds of BiVO4. The boosted TC degradation over CN/Na-BiVO4was ascribed to the Z-scheme heterojunction formation, doped Na+, more V4+and oxygen vacancies resulting from Na+doping facilitate the electron-hole pairs migration and separation. Meanwhile, more V4+and oxygen vacancies generated in Na-BiVO4also promoted the PMS activation. Therefore, a large number of reactive oxygen species (ROSs), including •O2−, h+, •OH, SO4•−, and 1O2, were produced in CN/Na-BiVO4+PMS+Vis system to degrade TC. The mechanism of enhanced PMS-assisted photocatalytic degradation of TC was proposed. This work further highlighted the advantages of the PMS-assisted photocatalytic technology in antibiotics removal and also demonstrated that g-C3N4coupling and Na doping co-modify BiVO4was one effective and feasible method for promoting the PMS-assisted photocatalytic degradation of TC under visible light.