Pilot production of a sensitive ELISA kit and an immunochromatographic strip for rapid detecting citrinin in fermented rice

Shih-Wei Wu; Jiunn-Liang Ko; Biing-Hui Liu; Feng-Yih Yu

doi:10.1039/d2ra02823a

Pilot production of a sensitive ELISA kit and an immunochromatographic strip for rapid detecting citrinin in fermented rice

RSC Adv. 2022 Jul 8;12(31):19981-19989. doi: 10.1039/d2ra02823a. eCollection 2022 Jul 6.

Authors

Shih-Wei Wu¹, Jiunn-Liang Ko¹, Biing-Hui Liu², Feng-Yih Yu^{3

4}

Affiliations

¹ Graduate Institute of Medicine, Chung Shan Medical University Taichung 40201 Taiwan.
² Graduate Institute of Toxicology, College of Medicine, National Taiwan University Taipei 10051 Taiwan biingliu@ntu.edu.tw +886-2-23123456-88602.
³ Department of Medical Research, Chung Shan Medical University Hospital Taichung 40201 Taiwan.
⁴ Department of Biomedical Sciences, Chung Shan Medical University Taichung 40201 Taiwan fengyu@csmu.edu.tw +886-4-24730022-11816.

Abstract

Citrinin (CTN) is a mycotoxin primarily produced by Monascus species. Excess consumption of CTN may lead to nephrotoxicity and hepatotoxicity. A pilot study for commercial production of competitive direct enzyme-linked immunosorbent assay (cdELISA) kit and an immunochromatographic strip (immunostrip) for screening CTN in red yeast rice is established in this study. The coating antibody and the CTN-horse radish peroxidase (HRP) concentrations were optimized to increase the sensitivity and specificity of cdELISA kit. The conjugation methods/ratios of CTN to HRP as well as the long-term stability of kit components were also evaluated. The IC₅₀ and detection limit of the ELISA kit were determined to be 4.1 and 0.2 ng mL^-1, respectively. Analysis of 20 red yeast rice samples using ELISA kits revealed the contamination levels of CTN from 64 to 29 404 ng g^-1. The on-site rapid detection of CTN with the immunostrip showed that CTN levels in seven samples exceeded the regulatory limit of 5 ppm. Additionally, the coefficient correlation between the results of HPLC and ELISA kits of 20 samples was 0.96. Sensitive and convenient tools at commercial levels for detection of CTN contamination in food are established herein to protect the health of the public.