摘要
建立一种基于生物条形码探针和金纳米颗粒(gold nanoparticles,AuNPs)对致病性大肠杆菌O157:H7检测的新方法。用生物功能化的磁性纳米颗粒(magnetic nanoparticles,MNPs)和AuNPs与目标物大肠杆菌O157:H7进行免疫反应,形成MNPs/目标物/AuNPs"三明治"式复合体。利用去杂交将AuNPs上标记的条形码DNA释放出来,通过DNA探针杂交条形码DNA引起AuNPs颜色变化来确定大肠杆菌O157:H7的存在,这种颜色变化很容易用裸眼观察到并且可以通过紫外-可见吸收光谱定量分析,该方法在纯样品和牛奶中最低检测限为102CFU/mL,检测范围为102～106CFU/mL。应用基于生物条形码探针和AuNPs对大肠杆菌O157:H7检测具有准确、快速、操作简单的优点,为食品安全监测提供了新的方法。
A novel assay was developed for the detection of Escherichia coli O157：H7（E.coli O157：H7）based on bio-bar DNA and gold nanoparticles（AuNPs）.The immune reaction between the target and antibodies modified on biofunctionalized magnetic nanoparticles（MNPs）or AuNPs leads to the formation of a sandwich structure of MNPs/target/AuNPs,followed by dehybridization and release of bio-bar DNA.Due to its ability to hybridize with probe ssDNAs modified on AuNPs,bio-bar DNA could lead to aggregation and color change of AuNPs,which is readily visible with naked eyes,and can be quantified by UVvisible spectroscopy as well.The proposed method had a detection limit of about 102 CFU/mL in both pure broth culture and milk with a detection range of 102-106 CFU/mL.With the aid of bio-bar DNA and AuNPs,detection of E.coli O157：H7 in food is accurate,fast,and easy-operated,which may provide a new tool for food safety monitoring.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2011年第8期177-181,共5页
Food Science
基金
国家自然科学基金青年项目(20805020)
教育部科学技术研究重点项目(109079)
食品科学与技术国家重点实验室开放课题(SKLF-KF-200809)
