State Key Laboratory for Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, 300457, China.
Anal Methods. 2022 May 19;14(19):1872-1879. doi: 10.1039/d2ay00158f.
A fluorescence detection method based on quantum dot-aptamer-graphene oxide probes (QD-Apt-GO) was developed to detect β-lactoglobulin (β-LG) in foods. When β-LG was present in the samples, it specifically bound to the aptamer, inhibiting the binding of probes to graphene oxide (GO), and the fluorescence of the probes could be detected. When β-LG was not present, the probes could bind to GO through π-π stacking, and the fluorescence was consequently quenched. The detection range of the optimized assay for β-LG detection was 0.36-500 mg L. The limit of detection (LOD) for β-LG was 96.91 μg L. The method was also validated for food sample detection. In the spike and recovery experiments of Neocate amino acid infant formula, infant millet cookies, and infant rice porridge, the recoveries were in the range of 83.33-114.53%, which met the required range of the addition recoveries. At the same time, the results were consistent with those of commercial ELISA kits. Three types of random food products purchased from a local market were analyzed for β-LG the developed assay and using a commercial ELISA kit. The results showed good accuracy and consistency between the proposed method and the commercial ELISA kit.
基于量子点-适体-氧化石墨烯探针(QD-Apt-GO)的荧光检测方法被开发用于检测食品中的β-乳球蛋白(β-LG)。当样品中存在β-LG 时，它会特异性地与适体结合，抑制探针与氧化石墨烯(GO)的结合，从而可以检测到探针的荧光。当β-LG 不存在时，探针可以通过π-π 堆积与 GO 结合，从而导致荧光猝灭。优化后的β-LG 检测分析方法的检测范围为 0.36-500mg/L。β-LG 的检测限(LOD)为 96.91μg/L。该方法还经过了食品样品检测的验证。在 Neocate 氨基酸婴儿配方奶粉、婴儿小米饼干和婴儿米粥的加标和回收实验中，回收率在 83.33%-114.53%范围内，符合添加回收率的要求范围。同时，与商业 ELISA 试剂盒的结果一致。从当地市场购买的三种随机食品分别用开发的检测方法和商业 ELISA 试剂盒分析了β-LG。结果表明，该方法与商业 ELISA 试剂盒具有良好的准确性和一致性。
