Department of Nutrition and Food Hygiene, School of Public Health, Health Science Center, Shenzhen University, Shenzhen 518060, China; State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Changchun 130022, China.
Shenzhen People's Hospital, Shenzhen 518020, China.
Food Chem. 2021 Sep 1;355:129443. doi: 10.1016/j.foodchem.2021.129443. Epub 2021 Mar 3.
Here, a facile hydrothermal method was used to synthesize highly photoluminescent N-doped carbon dots, and the quantum yields reached 97.1%. Then, a label-free immunosensor based on the inner filter effect of carbon dots was developed for ultrasensitive detection of aflatoxin M residues in milk. The detection limit was 0.0186 ng/mL (equivalents to 18.10 ng/kg), which satisfied the most stringent maximum tolerable limit value of 25 ng/kg. Besides, the immunosensor showed a good linear relationship from 0.003 ng/mL to 0.81 ng/mL, and the average recoveries ranged from 79.6% to 112.5% for spiked milk samples, with relative standard deviations ranging from 6.7% to 13.3%. Compared with other immunoassays, the inner filter effect-based immunosensor incorporating fluorescent detection into conventional enzymatic cascade amplification systems and could be a reliable on-site screening method for aflatoxin M residue analysis.
在这里，我们采用了一种简便的水热法来合成具有高光致发光性能的氮掺杂碳点，其量子产率高达 97.1%。然后，我们基于碳点的内滤效应开发了一种无标记免疫传感器，用于超灵敏检测牛奶中的黄曲霉毒素 M 残留。检测限为 0.0186ng/mL（相当于 18.10ng/kg），满足最严格的最大允许限量值 25ng/kg。此外，该免疫传感器在 0.003ng/mL 至 0.81ng/mL 范围内呈现良好的线性关系，对于添加的牛奶样品，平均回收率范围为 79.6%至 112.5%，相对标准偏差范围为 6.7%至 13.3%。与其他免疫分析方法相比，基于内滤效应的免疫传感器将荧光检测与传统的酶级联扩增系统相结合，可能成为一种用于黄曲霉毒素 M 残留分析的可靠现场筛选方法。
