To develop a colloidal gold strip for detection of Listeria monocytogenenes (LM) based on the monoclonal antibody against LM internalin A (InlA) protein.MethodsAfter analyzing the antigenic epitopes of LM inlA full-length gene encoded protein using DNAStar software, the target inlA gene fragment was selected to construct the prokaryotic expression plasmid, and the recombinant InlA protein was prepared by inducible expression and used to immunize the BALB/c mice. The specific monoclonal antibody against LM InlA protein was prepared. Based on the principle of double-antibody sandwich method, the colloidal gold strip was developed, and its specificity, sensitivity, and stability were evaluated. ResultsTwo hybridoma cell lines were identified to specifically secret anti-InlA monoclonal antibodies, and the antibody subclasses were IgG1subtype. The antibody titers of acites were 1∶64000. The colloidal gold strip showed positive reaction with the LM strains, but showed negative reactions with Listeria other than LM, as well as other food-borne bacteria such as Streptococcus, Salmonella typhimurium and EHEC O157∶H7. The detection limits for LM pure cultures and analog samples were 2.4×10⁵and 4.0×10⁶cfu/ml, respectively. The strip could be stored at 4℃ for more than 16weeks.ConclusionThe colloidal gold strip could be used to detect LM in food sample rapidly, sensitively and accurately.