大肠杆菌O157多克隆抗体及食品中双抗ELISA测定方法的研究

Studies on the polyclonal antibody and the double-antibody enzyme-linked immunosorbent assay against E.coli O157 in food

本研究获得了抗肠出血性大肠杆菌O157:H7的多克隆抗体 ,建立了一种适宜食品样品检测的双抗ELISA检测方法。该方法对纯培养菌液检出限为 10 3 ～ 10 4 cfu ml;只对O157菌株有特异性反应 ,对非O157菌株无交叉反应 ;经过增菌 ,鸡肉与牛奶染菌样品中的大肠杆菌O157的检出限均为 0 1cfu g(cfu ml)。

The polyclonal antibody (PcAb) for E.coli O157:H7 was available by i ntravenous injection with New Zealand rabbit with E.coli O157:H7 ATC C43895 strain. Together with the monoclonal antibody (McAb) 3A5 specific against E.coli O157 and O113:H21, a double-antibody sandwich enz yme-linked immunosorbent assay (ELISA) was developed with the as the capture an tibody and the McAb 3A5 as the detection antibody. The detection limits are 10 3-10 4 cfu/ml in pure culture of E.coli O157 and without any cross re action with the non-O157 strains. With 10h enrichment procedure, E.coli O157:H7 recovered well from inoculated ground poultry meat and pasteu rized milk at levels of 0.1 cfu/g(cfu/ml). The results demonstrated that the d ouble-antibody sandwich ELISA is a sensitive and specific method for detecting E.coli O157 in food samples.