斑点免疫金渗滤法检测沙门菌的研究与应用

Application and Rresearch of Dot Immunogold Filtration Assay for the Detection of Salmonella

〔目的〕研究一种特异性强,灵敏度高,且操作简便,快速的沙门菌检测方法,以用于临床样品中沙门菌的快速检测,并能在基层推广应用。〔方法〕应用胶体金标记纯化的兔抗沙门菌抗体-1,SPA(金黄色葡萄球菌A蛋白)包被硝酸纤维素膜作对照点,建立直接检测沙门菌的斑点免疫金渗滤法(DIGFA)检测试纸盒。〔结果〕通过胶体金标记兔抗沙门菌抗体直接显色,阳性者出现红色斑点,结果易于判断。整个试验过程仅需10￣15min即可判断结果,操作简单,与大肠埃希菌、枸橼酸杆菌、变形杆菌和绿脓杆菌等不发生交叉反应。沙门菌的最低检测量为4.5×106cfu/ml。同时将该法与国标法检测效果比较,符合率达100%。将胶体金标记的兔抗沙门菌抗体冻干粉4℃存放12个月,检测结果无差异。〔结论〕研究结果表明该法具有微量、特异、敏感、快速可靠,效果直观,判断容易,无需特殊仪器设备,非常适用于沙门菌的快速检测,值得推广应用。

Objective To establish a rapid and simple method with high sensitivity and specificity for detecting salmonella especially for the setting at grass root level. Methods The dot immunogold filtration assay （DIGFA） was developed by coating clinic sample on nitrocellulose （NC） membrane, spraying SPA on control dot, labeling rabbit anti-salmonella IgG -1 with colloidal gold. Results If detected sample contains salmonella, the detection dot appears red spot. The whole test procedure could be finished in only 10-15minutes. The method has a better specificity and no cross-reaction with other enterobacteria such as Escherichia coli, proteus mirabilis,Citrobacter freundii,Enterobacter cloacae, its sensitivity is 4.5×10^6 cfu/ml. It can be Stored at 4℃ for 12 months and accord with native criteria. Concuision The DIGFA has a simple,rapid,high sensitive,strongly specific characteristics. There is no need for a specific instrument and facilitie, and its result is easily observed and determined. It is good worthy to use it widely, especially in small diagnostic laboratories.