啶虫脒金标免疫速测试纸条研制及其在茶叶中的应用

阐述了一种基于直接竞争免疫层析法的啶虫脒金标速测试纸条的研制方法,及其在茶叶中快速检测与诊断啶虫脒残留的应用情况。通过制备啶虫脒人工抗原,获得了高灵敏度的单克隆抗体,抗体效价大于1:10000。据此研制的金标速测试纸条对啶虫脒肉眼判断的检出限为10ng/mL,检测时间为10min;可特异性地检测茶叶(绿茶、红茶、铁观音)中烟碱类农药啶虫脒的残留量,而对其他烟碱类农药(吡虫啉、噻虫嗪、烯啶虫胺等)无交叉反应,能满足中国茶叶中啶虫脒最大残留限量(0.5mg/kg)下的检测要求,具有灵敏度高、使用便捷、结果准确、成本低等优点。该技术可以实现成品茶样品中啶虫脒的现场快速测试诊断。

Development and application of gold immunostrip for the detection of acetamiprid residue in tea samples

The development of a gold immunostrip for the rapid detection of acetamiprid residue in tea samples was described. It was based on the principle of direct competitive immunochromatography. The artificial antigen of acetamiprid was prepared for immunization, and a highly-sensitive monoclonal antibody was obtained with the titer of 1:10 000. Subsequently, the gold immunostrip was developed and the visual detection limit of acetamiprid was 10 ng/mL. The detection time was just 10 min. No cross reaction with other neonicotinoid pesticides, such as imidacloprid, thiamethoxam, and nitenpyram, was detected. Moreover, this method has been used to determine the acetamiprid residue in tea (green tea, black tea and extra-strong tea) by spiked recovery tests. And results indicated that this method could meet the detection requirement of Chinese MRL of acetamiprid (0.5 mg/kg) in tea. Also, it possessed some advantages such as high efficiency, convenience, and low cost. Overall, the newly-developed immunostrip can be used in field tests for rapid screening of fresh tea before tea harvest and the quality control of tea products.