基于 CdSe/ZnS 量子点标记的单克隆抗体的荧光免疫吸附法检测乳制品中的α-乳白蛋白

Fluorescent immunosorbent assay for the detection of alpha lactalbumin in dairy products with monoclonal antibody bioconjugated with CdSe/ZnS quantum dots.

机构信息

State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China; Sino-German Joint Research Institute, Nanchang University, Nanchang 330047, China.

出版信息

Food Chem. 2014 May 1;150:73-9. doi: 10.1016/j.foodchem.2013.10.137. Epub 2013 Nov 4.

DOI:10.1016/j.foodchem.2013.10.137

PMID:24360421

Abstract

In this work, a new method termed competitive fluorescence-linked immunosorbent assay (FLISA) was developed for specifically quantification of bovine α-lactalbumin (α-La) in dairy products. The monoclonal antibodies (mAbs) against α-La were produced through hybridoma technology, and the mAbs were covalently conjugated with the CdSe/ZnS quantum dots (QDs) using the crossing-linking reagents. Moreover, a competitive FLISA based on QD-mAb conjugates was established to detect α-La in dairy products. It was shown that there was a good linear relationship between inhibition efficiency, and logarithm of α-La concentration after the detection parameters were optimised in which the concentration of α-La varied from 0.1 to 1000ng/mL. The value of IC50 was 0.03μg/mL, and the FLISA method exhibited high sensitivity with the LOD at 0.1ng/mL. The developed FLISA has been successfully applied to determine α-La in commercial dairy products, providing more sensitive analysis compared with the ELISA method.

摘要

本工作建立了一种新的方法，即竞争荧光酶联免疫吸附测定法（FLISA），用于特异性定量检测乳制品中的牛α-乳白蛋白（α-La）。通过杂交瘤技术制备了针对α-La 的单克隆抗体（mAbs），并用交联试剂将 mAbs 与 CdSe/ZnS 量子点（QDs）共价偶联。此外，建立了基于 QD-mAb 偶联物的竞争 FLISA 来检测乳制品中的α-La。结果表明，在优化检测参数后，抑制效率与α-La 浓度的对数之间存在良好的线性关系，其中α-La 的浓度范围为 0.1 至 1000ng/mL。IC50 值为 0.03μg/mL，该 FLISA 方法具有较高的灵敏度，LOD 为 0.1ng/mL。该 FLISA 已成功应用于商业乳制品中α-La 的测定，与 ELISA 方法相比，提供了更灵敏的分析。