核酸适体结构转换荧光法检测黄曲霉毒素B_1

An Aptamer Struture Conversion Fluorescence Assay for the Detection of Aflatoxin B_1

基于黄曲霉毒素B_1(Aflatoxin B_1,AFB_1)与互补链竞争结合核酸适体的位点使荧光恢复,建立了核酸适体结构转换荧光法检测AFB_1。以PBS为工作液,200 nmol/L核酸适体与200 nmol/L猝灭链反应30min后加入AFB_1孵育1 h,利用荧光分光光度计检测到的荧光恢复程度对AFB_1进行定量检测,可获得该方法的最佳效果。在优化条件下,AFB_1检测浓度范围为1～300 ng/mL,检出限为0. 8 ng/mL。对该检测方法的特异性进行考察,结果表明该法具有良好的特异性。对花生、玉米实际样品进行检测,回收率在81. 1%～108. 3%之间。

An aptamer struture conversion fluorescence assay for the detection of Aflatoxin B1 was built based on AFB1 competed with complementary oligonucleotides to bind to aptamer that cause fluorescence recover. AFB1 was detected by fluorescence spectrophotometer through the fluorescence recovery phenomenon as follow condition:PBS acted as the working buffer. After 200 nmol/ L aptamer reacted with 200 nmol/ L quenching oligonucleotide for 30 min, add AFB1 in the detection system and incubated for 1 h. This way could achieve the best result. Under the optimum conditions,the linear range for the AFB1 concentration detection is 1 - 300 ng/ mL with a detection limit of 0. 8 ng/ mL. The specificity of the method was investigated and the result showed that was good. Taking peanut and corn as samples for recovery test,the recovery rate was between 81. 1%~108. 3%.