应用流式微球检测黄曲霉毒素B1方法的建立

采用活性酯法,将AFB1-BSA人工抗原交联于含有羧基表面的荧光微球,通过与游离AFB1竞争抗AFB1单克隆抗体后,再与异硫氰酸荧光素标记二抗的反应,建立基于微球的间接竞争免疫检测方法.检测结果表明,流式细胞仪检测AFB1的检测限为0.03 ng·mL-1,检测范围为0.05～1.0 ng·mL-1.与黄曲霉毒素B2、黄曲霉毒素G1、黄曲霉毒素G2、黄曲霉毒素M1和黄曲霉毒素M2的交叉反应率均低于1.0%.在玉米样品中的加标回收率为87%～103%,变异系数为6.1%～8.4%.

Determination of aflatoxin B1 based on a flow cytometric microsphere immunoassay

Carboxyl-modified microspheres internally dyed with fluroscent dye were conjugated with the artificial antigen AFB1-BSA.aflatoxin B1(AFB1) was used as a positive control to compete with the AFB1-BSA antigen on the surface of the microspheres for the anti-AFB1 McAb.A fluorescein isothiocyanate labeled IgG reporter antibody was added to react specifically with the anti-AFB1 McAb on the microspheres.The detection limit of AFB1 reached 0.03 ng·mL-1,with a good linearity ranging 0.05~1.0 ng mL-1.The cross-reactivity rates were less than 1.0% with other toxins such as aflatoxins B2,aflatoxins G1,aflatoxins G2,aflatoxins M1 and aflatoxins M2.The recovery of AFB1 from artificially contaminated corn samples was from 89% to 92%,with CVs from 6.8% to 9.0%.A novel method for the determination of aflatoxin B1 by an indirect competitive immunoassay with a flow cytometer has been developed.