畜禽产品中甲氧苄啶残留检测的方法研究OA

To improve the efficiency of trimethoprim(TMP)residue detection in livestock and poultry products,an analytical method was developed using high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)combined with pass-through solid-phase extraction(SPE)for the determination of TMP residues.Meat and egg samples were extracted with acidified acetonitrile-water,salted out with Na2SO4,and purified using EMR-Lipid SPE cartridges.Chromatographic separation was performed on a ZORBAX Eclipse Plus C18 column,and detection was carried out using electrospray ionization in positive ion mode under multiple reaction monitoring,with quantification by external standard method.The results demonstrated good linearity for TMP in the ranges of 1-20 μg/L for meat and 0.25-5.0 μg/L for eggs,with correlation coefficients larger than 0.99.The limits of detection(LOD)were 0.5 μg/kg for meat and 0.1 μg/kg for eggs,and the limits of quantification(LOQ)were 1.0 μg/kg for meat and 0.2 μg/kg for eggs.At low,medium,and high spiking levels,the recoveries of TMP ranged from 70%to 120%with relative standard deviations(RSD)≤15%in meat matrices,and from 60%to 120%with RSD≤20%in egg matrices.Compared with the standard method,statistical analysis and t-test showed P>0.05,indicating no statistically significant difference and confirming that the method meets the requirements for method equivalence validation.This study provides robust technical support for veterinary drug residue monitoring and food safety control.