科研之友
微信
新浪微博
Facebook
分享链接
摘要
Methods based on potentiometric measurement have been developed for immunoassays, but most exhibit low sensitivities and are unsuitable for early diagnosis of disease. Herein we design a new potentiometric immunosensing platform for the sensitive detection of carcinoma antigen 15-3 (CA 15-3) by coupling with enzymatic biocatalytic precipitation and a nanogold labeling technique. The sandwich-type immunoreaction is carried out on a monoclonal anti-CA 15-3 capture antibody-modified working electrode, using horseradish peroxidase (HRP) and polyclonal anti-CA 15-3 detection antibody-labeled gold nanoparticles. Upon the introduction of target CA 15-3, the carried HRP molecules with an immunocomplex catalyze the oxidation of 4-chloro-1-naphthol (4-CN) into the insoluble benzo-4-chlorohexadienone. The formed product coated on the surface of the modified electrode results in a change of the electrical potential. Under optimal conditions, the shift in the electrical potential relative to the background signal increases with the increasing target CA 15-3 concentration, and exhibits a good linear relationship within the dynamic range of 0.01-30 U mL(-1) at a detection limit of 7.8 mU mL(-1). Good precision and reproducibility, and high specificity were acquired for the analysis of 15 human serum specimens, giving well matched results with those obtained from a human CA 15-3 ELISA kit.
- 出版日期2018-3-21
- 单位重庆医科大学
