Competitive plasmonic biomimetic enzyme-linked immunosorbent assay for sensitive detection of bisphenol A

A plasmonic biomimetic enzyme-linked immunosorbent assay (PBELISA) method was developed for ultrasensitive and on-site visual detection of bisphenol A (BPA). The PBELISA was an enzyme-linked immunoassay using molecularly imprinted polymer (MIP) film as biomimetic antibody combined with catalase (CAT)-mediated growth of plasmonic gold nanoparticles (AuNPs). With the BPA concentration increased, a distinguished color change was observed from colorless to blue and then red. Therefore, the proposed method could be employed with naked-eye observation to detect BPA with visual limit of detection (LOD) of 40 pg/mL. For quantitative analysis, this method also exhibited a good dynamic linear response to the logarithmic BPA concentrations ranged from 10 pg/mL to 1.024 x 10(4) pg/mL with a correlation coefficient of R-2 = 0.9922 and LOD of 6.20 pg/ mL. The recovery rates in tap water, milk and orange juice ranged from 91.83% to 107.39%. In brief, the developed PBELISA method is sensitive, cost-effective and easy-to-use for BPA detection.

Automated summary

The PBELISA method using plasmonic biomimetic technology combined with MIP film and CAT-mediated AuNPs growth achieved ultra-sensitive visual detection of BPA; with a visual limit of detection of 40 pg/mL, the method showed good dynamic linear response and high recovery rates.