基于信标免疫磁颗粒和纳米金放大的压电免疫传感器检测大肠埃希菌0157:H7

【作者】 谌志强； 王景峰； 邱志刚； 金敏； 王新为； 陈照立； 李君文； 晁福寰；

【机构】 军事医学科学院卫生学环境医学研究所；

【摘要】 目的建立检测大肠杆菌O157:H7高灵敏检测技术。方法在纳米磁颗粒连接上按一定比例混合的目标抗体和信标抗体制成信标免疫磁颗粒,使其具有捕获目标细菌、连接亲和素标记的胶体金和质量放大的作用;通过溴化十六烷基三甲铵(CTAB)法制备金生长液;采用SPA法修饰压电免疫传感器,压电免疫传感器的频率信号得到了信标免疫磁颗粒、胶体金和金生长液的多级放大。结果信标免疫磁颗粒上目标抗体和信标抗体的最佳比例为1:60,最佳使用体积为20μl,大肠杆菌O157:H7的检测灵敏度为23 CFU/ml。结论信标免疫磁颗粒等对压电免疫传感器的频率具有很好的放大效应,可以明显提高其检测灵敏度。更多还原

【Abstract】 Objective We developed a sensitive method to detect Escherichia coli 0157:H7. Method E.coli O157-BIMPs were magnetic nanoparticles loaded with target antibody and beacon antibody at one ratio,which had 3 functions:capturing target cells, conjugating streptavidin-gold,and mass enhancement.The growth solution was prepared using CTAB.The immunosensor was fabricated using SPA.The frequency shift of a QCM immunosensor was multi-amplified using beacon immunomagnetic nanoparticles(BIMPs),streptavidin-gold,and growth solution.Result The most suitable ratio of target antibody and beacon antibody was 1:60,and the suitable volume of the E.coli O157-BIMPs was 20μl.The detection limit was 23 CFU/ml.Conclusion The prepared E.coli O157-BIMPs might be used to significantly amplify the frequency signal of the piezoelectric immunosensor and improve the detect sensitivity.更多还原