Abstract:Cephalosporin antibiotics are the second type of β -lactam antibiotics.It is extremely easy for animal-derived food to be contaminated with cephalosporin antibiotics，resulting in an increasing public attention.In this study，a nitrocellulose membrane-based immunochromatographic test trip was constructed for multi-residues determination of 3 kinds of cephalosporin antibiotics.In this test strip，AuNPs modified anticephalexin rabbit polyclonal antibody was applied as the visual probe；the cephalexin antigen and the antirabbit goat antibody was used as the control line and the test line，respectively.Under the optimized experimental conditions，the detection limits of this test strip towards cephalexin，cephradine，and cefadroxil were 20，25，25 μg/L，respectively.To verify the practicability of this developed test strip，we added a certain concentration of cephalexin in shrimp，milk，beef，pork，raw pig liver，and cooked pig liver sample for recovery test.The results showed that，after a sample pretreatment，the test strip provided the visual signals within 10 minutes.The established method in this study was simple and rapid，and was suitable for rapidly screening large numbers of animal-derived food samples.