High Throughput Screening of Tranquilizers in Dairy Products Using Ultra-Performance Liquid Chromatography Coupled to High Resolution Time-of-Flight Mass Spectrometry

Synthesis of azo-linked covalent organic polymers for pipette tip solid-phase extraction of sedative residues from animal tissues samples

Azo-linked covalent organic polymers (ACOPs) were synthesized by a simple azo reaction, with 2,2'-bis(trifluoromethyl)benzidine and 1,3,5-trihydroxybenzene as the monomers. The preparation process was mild, green, and environmental-friendly, avoiding the use of high temperature, metal catalysis, and harmful organic reagent. The obtained ACOPs were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and Brunauer-Emmett-Teller. With the prepared ACOPs as adsorbent, a method of pipette tip solid-phase extraction-liquid chromatography-tandem mass spectrometry detection (PTSPE-LC-MS/MS) was proposed for the analysis of target sedatives in animal tissues. Furthermore, the parameters for the extraction of five sedatives, including the amount of adsorbent, pH value, ion strength, elution solvent and volume, were investigated. Under the optimized conditions, the linear dynamic range was found from 0.1 to 10.0 μg kg-1, and the limits of detection were ranged from 0.02 to 0.1 μg kg-1. The method was assessed by the analysis of target sedatives in animal tissues, and the recoveries for the spiked pork muscle and pork liver samples were 84-102% and 83-101%, respectively. The results show that the developed method of PTSPE-LC-MS/MS with ACOPs as adsorbent is efficient for the analysis of trace sedatives in animal tissues.

Determination of 15 sedative residues in mutton by rapid resolution liquid chromatography-tandem mass spectrometry

BACKGROUND

The use of xenobiotic compounds in animal husbandry has given rise to consumer anxieties regarding residual risk and food safety. Thus, animal tissues have become main samples for residue analysis and food safety for sedatives. In this study, a rapid resolution liquid chromatography-tandem mass spectrometry (RRLC-MS/MS) method was established for the determination of 15 sedatives residues in mutton.

RESULTS

After enzymolysis, sedatives residues in mutton were extracted by ammonium hydroxide-acetonitrile (10:90, v/v) and determined by RRLC-MS/MS with quantification by standard curve method. The calibration curves showed good linearity within the concentrations of 0.5-50 µg kg(-1) with the correlation coefficients (r(2)) ranged from 0.9639 to 0.9984. The limits of detection (LODs) and quantification (LOQs) were 0.25-2.5 and 0.5-5 µg kg(-1), respectively. The average recoveries of spikes samples were in the ranges of 74.1-116.8% with relative standard deviations of intra- and inter-day ranged from 2.6% to 11.2% and from 2.1% to 11.4%, respectively.

CONCLUSION

This method is simple, sensitive and accurate in the determination of sedative residues.