State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
College of Materials, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China.
Food Chem. 2020 Nov 1;329:127160. doi: 10.1016/j.foodchem.2020.127160. Epub 2020 May 27.
In this study, we developed an indirect competitive plasmonic immunoassay using glucose oxidase (GOx)-induced redox reaction to etch Au nanorods (AuNRs) for qualitative and quantitative detection of aflatoxin M1 (AFM1) in milk. In this system, streptavidin (SA) was selected as a linker between biotinylated anti-AFM1-monoantibody (bio-mAb) and biotinylated GOx (bio-GOx) to form the immunocomplexes bio-mAb-SA-bio-GOx. After the oxidation of the glucose and I, the resultant I could etch cetytrimethylammonium bromide (CTAB)-stabilized AuNRs. This resulted in the blue shift of the longitudinal localized surface plasmon resonance (LSPR) extinction peak, with a color change from blue to pink. The linear range and limit of detection (LOD) of the plasmonic immunoassay were 0.25-10 ng mL and 0.11 ng mL, respectively. It displayed quantitative detection with high sensitivity, specificity, recovery, and accuracy, which is promising for qualitative and quantitative detection of AFM1 in food safety.
在这项研究中，我们开发了一种间接竞争等离子体免疫分析方法，利用葡萄糖氧化酶（GOx）诱导的氧化还原反应来刻蚀金纳米棒（AuNRs），用于定性和定量检测牛奶中的黄曲霉毒素 M1（AFM1）。在该体系中，链霉亲和素（SA）被选择作为生物素化抗 AFM1 单克隆抗体（bio-mAb）和生物素化 GOx（bio-GOx）之间的连接物，以形成免疫复合物 bio-mAb-SA-bio-GOx。在葡萄糖和 I 的氧化作用下，生成的 I 可以刻蚀十六烷基三甲基溴化铵（CTAB）稳定的 AuNRs。这导致纵向局域表面等离子体共振（LSPR）消光峰的蓝移，颜色从蓝色变为粉红色。等离子体免疫分析的线性范围和检测限（LOD）分别为 0.25-10ngmL 和 0.11ngmL。它显示出定量检测的高灵敏度、特异性、回收率和准确性，有望用于食品安全中 AFM1 的定性和定量检测。
