Liu Ying, Zhao Ying, Zhang Tianyi, Chang Yunyun, Wang Shuangjie, Zou Rubing, Zhu Guonian, Shen Lirong, Guo Yirong
Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Zhejiang University, Hangzhou, China.
Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China.
Front Chem. 2019 Feb 28;7:76. doi: 10.3389/fchem.2019.00076. eCollection 2019.
In this study, a rapid and sensitive immunochromatographic strip (ICS) assay, based on quantum dots (QDs), was developed for the qualitative and quantitative detection of acetamiprid in agricultural samples. Acetamiprid-ovalbumin conjugates (ACE-OVA) and goat anti-mouse IgG were sprayed onto a nitrocellulose membrane as a test and control line. Two kinds of anti-acetamiprid monoclonal antibodies (mAb) obtained in our lab were characterized by the ELISA and surface plasmon resonance assay. The competitive immunoassay was established using a QDs-mAb conjugate probe. The visual detection limit of acetamiprid for a qualitative threshold was set as 1 ng/mL to the naked eye. In the quantitative test, the fluorescence intensity was measured by a portable strip reader and a standard curve was obtained with a linear range from 0.098 to 25 ng/mL, and the half maximal inhibitory concentration of 1.12 ng/mL. The developed method showed no evident cross-reactivities with other neonicotinoid insecticides except for thiacloprid (36.68%). The accuracy and precision of the developed QDs-ICS were further evaluated. Results showed that the average recoveries ranged from 78.38 to 126.97% in agricultural samples. Moreover, to test blind tea samples, the QDs-ICS showed comparable reliability and a high correlation with ultra-performance liquid chromatography-tandem mass spectrometry. The whole sample detection could be accomplished within 1 h. In brief, our data clearly manifested that QDs-ICS was quite qualified for the rapid and sensitive screening of acetamiprid residues in an agricultural product analysis and paves the way to point-of-care testing for other analytes.
在本研究中，开发了一种基于量子点（QDs）的快速灵敏免疫层析试纸条（ICS）检测方法，用于定性和定量检测农产品中的啶虫脒。将啶虫脒-卵清蛋白偶联物（ACE-OVA）和山羊抗小鼠IgG喷印在硝酸纤维素膜上作为检测线和对照线。用酶联免疫吸附测定法（ELISA）和表面等离子体共振测定法对本实验室获得的两种抗啶虫脒单克隆抗体（mAb）进行了表征。使用量子点-单克隆抗体偶联物探针建立了竞争免疫测定法。啶虫脒的肉眼定性检测限设定为1 ng/mL。在定量检测中，用便携式试纸条读数仪测量荧光强度，得到线性范围为0.098至25 ng/mL的标准曲线，半数最大抑制浓度为1.12 ng/mL。所开发的方法除了与噻虫啉（36.68%）外，与其他新烟碱类杀虫剂没有明显的交叉反应。进一步评估了所开发的量子点免疫层析试纸条（QDs-ICS）的准确性和精密度。结果表明，农产品样品中的平均回收率在78.38%至126.97%之间。此外，为了检测盲样茶叶，量子点免疫层析试纸条（QDs-ICS）显示出相当的可靠性，并且与超高效液相色谱-串联质谱法具有高度相关性。整个样品检测可在1小时内完成。简而言之，我们的数据清楚地表明，量子点免疫层析试纸条（QDs-ICS）完全有资格用于农产品分析中啶虫脒残留的快速灵敏筛选，并为其他分析物的即时检测铺平了道路。
