Novel Latex Microsphere Immunochromatographic Assay for Rapid Detection of Cadmium Ion in Asparagus

Foods

Xinlin Wei¹  Naifeng Xu²  Qiaojuan Zhu²  Jingze Jia²  Yuanfeng Wang²  Jiangxiong Zhu² 

[1] Department of Food Science & Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China;Institute of Engineering Food, College of Life Sciences, Shanghai Normal University, 100 Guilin Road, Xuhui District, Shanghai 200234, China;

关键词: cadmium ion;    monoclonal antibody;    immunochromatography;    latex microspheres;    asparagus;   

DOI  :  10.3390/foods11010078

来源: DOAJ

【 摘 要 】

Recently, concerns about heavy metal cadmium ion (Cd²⁺) residue in asparagus have been frequently reported, and there is an urgent need to develop an effective, sensitive, and rapid detection method for Cd²⁺. In this study, we innovatively combined molecular microbiology to carry out the comparative screening of Cd²⁺ chelators in a green, efficient, and specific way. The knock-out putative copper-transporter gene (pca1Δ) yeast strain with high sensitivity to Cd²⁺ was first used to screen the Cd²⁺ chelator, and the optimum chelator 1-(4-Isothiocyanatobenzyl)ethylenediamine-N,N,N,N′-tetraacetic acid (ITCBE) was obtained. Additionally, a rapid latex microsphere immunochromatographic assay (LMIA) was developed, based on the obtained monoclonal antibody (mAb) with high specificity and high affinity (affinity constant Ka = 1.83 × 10¹⁰ L/mol), to detect Cd²⁺ in asparagus. The 50% inhibitive concentration (IC₅₀) of test strip was measured to be 0.2 ng/mL, and the limit of detection (IC₁₀) for qualitative (LOD, for visual observation) and quantitative detection (LOQ, for data simulation) of the test strip was 2 ng/mL and 0.054 ng/mL, respectively. In all, the developed mAb-based LMIA shows a great potential for monitoring Cd²⁺ in asparagus, even in vegetable samples.

【 授权许可】

Unknown