A high sensitive chemiluminescent magnetic enzyme-linked immunoassay method was established for Escherichia coli O157∶H7 determination.The bacterium antibody was labeled by alkaline phosphatase（ALP） that catalyzed the decomposing of substrate 3-（2-spiroadamantane）-4-methoxy-4（3-phosphoryloxy）phenyl-1,2-dioxetane（AMPPD） to give the light emission.The sensitivity of the method is 8.5×104 Cell/mL with a linear range of 1.0×105—5.0×107 Cell/mL.The intra- and inter-assay CVs are 14.8% and 20.0% in pork samples, respectively.The correlation coefficient of present and the standard plate counting method is 0.981.The experiments with the spiked samples show that this method has great potential to be applied to（detecting） the concentration of Escherichia coli O157∶H7 in a variety of samples.
比较了几种荧光染料标记白色念珠菌和鼠伤寒沙门氏菌的效果及其对病菌生长和与H e la细胞粘附能力的影响,旨在为建立简便有效的荧光标记方法奠定基础。将2种致病菌分别在添加了罗丹明B、荧光素N a盐或吖啶橙的LB培养液,37℃条件下培养1 d,结果发现这2种致病菌都可以被荧光素N a盐标记,鼠伤寒沙门氏菌还可以被罗丹明B标记,但这2种致病菌都不能在吖啶橙中生长。测定致病菌荧光强度发现,随罗丹明B标记剂量的增加,致病菌荧光强度增强,而荧光素N a盐小剂量组处理的致病菌荧光强度最强。此外还发现,致病菌与H e la细胞的粘附不受荧光标记的影响。
