中文摘要：

目的建立基于盐酸羟胺晶种法的金增强的免疫渗滤法，快速、灵敏检测大肠埃希菌（Escherichiacoli）O157：H7。方法以柠檬酸钠还原法制备粒径约为18nm的免疫胶体金；采用羟胺晶种法对胶体金粒子进行生长放大，考察金生长液中盐酸羟胺与氯金酸的物质量的比对胶体金粒子生长放大的影响；借助透射电镜观察胶体金粒子在金生长前后大小形态的变化；利用金生长液对检测大肠埃希菌O157：H7的免疫渗滤结果进行金增强来提高其检测灵敏度。结果金生长液中盐酸羟胺与氯金酸的物质量的比为10：1，经过金生长液放大的胶体金粒子平均直径约为45nm，且形态较均一：经过金增强的免疫渗滤法检测大肠埃希菌O157：H7灵敏度达到了7．8×10^4 cfu／ml，且特异性强。结论盐酸羟胺晶种法制备的金生长液可显著提高免疫渗滤方法的检测灵敏度。

英文摘要：

Objective-To develop-arapidand-sensitive method for the detection Escherichia coli O157：H7 based on gold-enhanced dot immuno-gold filtration assay by seeding growth with hydroxylamine hydrochloride. Methods About 18 nm colloid gold was prepared by sodium citrate reduction; The colloid gold particles were enlarged by using a mixture of HAuCl4 and NH2OH· HCl, and the relation between colloid gold particles and molar ratio of HAuCl4 and NH2·OH HC was investigated; The growth of colloidal gold particles in gold before and after the change in size and shape was observed by transmission electron microscope; The sensitivity of detection of Escherichia coli 0157 ：H7 with dot immuno-gold filtration assay was increased by gold-enhanced. Results The molar ratio of [HAuCl4]：[NH2OH·HC1] was 10：1. The size of colloid gold particles was about 45 nm after growthing. The sensitivity of detection of Escherichiacoli O157：H7 with dot immuno-gold filtration assay by gold-enhanced was 7.8×10^4 efu/ml, and the specificity was high. Conclusion The gold solution growth based on seeding growth with hydroxylamine hydrochloride can remarkably increase the sensitivity of dot immuno-gold filtration assay.