玉米赤霉烯酮的高灵敏时间分辨荧光免疫分析

采用时间分辨荧光技术建立高灵敏的玉米赤霉烯酮（ZEN）间接竞争免疫分析法（ZEN-TRFIA）。以玉米赤霉烯酮人工抗原（ZEN-BSA）包被96孔板为固相抗原，与ZEN标准或样品中的ZEN共同竞争有限的抗ZEN的单抗；用稀土离子Eu3+标记的羊抗鼠抗体进行示踪。该方法的灵敏度为0.01 μg/L（10ppt），测量范围为0.01-20 μg/L，批内和批间变异分别为7.2%和14.6%，平均回收率为94.4%，与玉米赤霉醇（ZER）的交叉反应率为15.16%。7条不同时间进行的ZEN-TRFIA的效应点值ED20、ED50、ED80分别为0.156±0.035 μg/L、0.634±0.091 μg/L和2.595±0.274 μg/L。试剂盒4℃保质期超过6个月。研究表明，ZEN-TRFIA是目前报导的ZEN检测中较灵敏的方法，该分析方法稳定性好，货架期符合要求，可测范围宽，具有很好的应用前景。

Ultrasensitive Time-resolved Fluoroimmunoassay of Zearalenone

In order to provide a rapid, selectivity and very high sensitivity method for the determination of zearaleone(ZEN), a competitive indirect time-resolved fluoroimmunoassay(TRFIA) was used. An immunogen of ZEA-oxime-BSA conjugate coated onto the microtitre plate competes with ZEN standard controls or free ZEN in the sample for anti-ZEN antibody. A goat antirat IgG-Eu3+ conjugate was used to enable detection. The suitability of the assay for quantification of ZEN was also studied. Results showed the limit of detection of the assay to be 0.01μg/L(10ppt) for indirect competitive TRFIA formats. The assay range was 0.01-20 μg/L. The concentration of ZEN that is required for 20%, 50% and 80% binding inhibition (ED20, ED50, ED80) were 0.156±0.035 μg/L, 0.634±0.091 μg/L and 2.595±0.274 μg/L, respectively. Cross-reactivity of Zearalanol was 15.16%. The inter- and intra-assay variability of the ZEN-TRFIA were 7.2% and 14.6%, respectively. The mean recovery of ZEN from corn samples was 94.4%. The kit can be stored at 4℃over 6 months. It was shown that the newly developed TRFIA could be applied to detect the ZEN contamination in corn. The ZEN-TRFIA provides very high sensitivity and optimal range, it will be useful to screen ZEN contamination easily, simply and economically when the the number of sanples is large.