High through-put determination of 28 veterinary antibiotic residues in swine wastewater by one-step dispersive solid phase extraction sample cleanup coupled with ultra-performance liquid chromatography-tandem mass spectrometry

Single and joint toxic effects of four antibiotics on some metabolic pathways of zebrafish (Danio rerio) larvae

In China, antibiotics are commonly used for human and veterinary medicine, and they are present in various environmental media. Thus, the toxic effects of antibiotics on organisms have attracted the attention of society and scientists alike. In this study, zebrafish embryos were used to test the single and joint toxicity of four antibiotics, sulfamonomethoxine (SMM), cefotaxime sodium (CFT), tetracycline (TC), enrofloxacin (ENR), and their combinations, combining the results of experimental and omics techniques. Following exposure to antibiotics for 120 h, the body lengths of zebrafish larvae in all 100 μg/L antibiotic groups were significantly shortened, and the reactive oxygen species (ROS) content in the 100 μg/L Mix group was significantly increased. Transcriptome sequencing (RNA-seq) showed that the mRNA level of numerous genes was significantly changed in the five antibiotic treatment groups. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of the differentially expressed genes revealed a significant enrichment of the steroid biosynthesis and other metabolism pathways. Hub gene analysis highlighted dhcr24, acat1, aldh1a2, aldh8a1, suclg2, hadh, and hsdl2 as the key genes, and hub gene expression changes because of the antibiotic treatment suggested that the metabolic system of the zebrafish larvae was severely disrupted by the interaction with other genes. In conclusion, single or joint exposure to different antibiotics at environmental concentrations affected the early development and metabolic system of zebrafish larvae, and our results provide fundamental evidence for future studies of antibiotic toxicity in aquatic organisms.

Trends in sensitive detection and rapid removal of sulfonamides: A review

Sulfonamides in environmental water, food, and feed are a major concern for both aquatic ecosystems and public health, because they may lead to the health risk of drug resistance. Thus, numerous sensitive detection and rapid removal methodologies have been established. This review summarizes the sample preparation techniques and instrumental methods used for sensitive detection of sulfonamides. Additionally, adsorption and photocatalysis for the rapid removal of sulfonamides are also discussed. This review provides a comprehensive perspective on future sulfonamide analyses that have good performance, and on the basic methods for the rapid removal of sulfonamides.

New matrix certified reference material for accurate measurement of ciprofloxacin residue in egg

Matrix certified reference materials (CRMs) are an indispensable part of method validation and have played an important role in ensuring reliable analytical results. To retain similarity to real samples, a new matrix CRM for the mass fraction of ciprofloxacin in whole liquid egg was developed by use of incurred materials with a target value corresponding to residue levels in real sample. The source materials were collected from laying hens following oral administration of ciprofloxacin. An optimized homogenization method and a strict bottling process were applied to bulk whole egg materials to prepare the CRM candidate. The mass fraction of ciprofloxacin in whole liquid egg was certified by a collaborative characterization program with eight accredited participating laboratories. Liquid chromatography coupled with isotope dilution mass spectrometry was studied as a reliable reference method for value assignment and was used by all participating laboratories. The certified value and expanded uncertainty (k = 2, at a confidence level of 95%) was 39.7 ± 5.2 μg/kg for ciprofloxacin in whole liquid egg. Homogeneity, long-term stability at -70 °C for 12 months, and short-term stability at -18 °C, 4 °C, and room temperature were assessed for 9 days. Additionally, uncertainties arising from inhomogeneity, instability, and characterization were analyzed in detail and fully estimated. This CRM would be a useful tool for validation of analytical methods and proficiency testing in ciprofloxacin residue analysis of egg. Graphical Abstract.