A novel aptasensing method for detecting bisphenol A using the catalytic effect of the Fe3O4/Au nanoparticles on the reduction reaction of the silver ions

The gold electrode was functionalized with anti-bisphenol A (BPA) aptamer and captured the BPA as analyte. By dropping the aptamer-modified magnetic Fe3O4/Au nanoparticles solution onto the electrode, a BPA molecule attaches to many aptamers that are in contact with a large number of Fe3O4/Au nanoparticles. The modified electrode were transferred to a solution containing Ag+ ions. Fe3O4/Au nanoparticles reduce the Ag+ ions to Ag0. A potential scan was applied for the oxidation of the Ag0-loaded magnetic nanoparticles to the AgCl. The magnitude of the stripping anodic signal of the Ag0 was related to the concentration of the BPA. The assay shows a detection limit of 0.6 fmol L-1 and linear range of 1 fmol L-1-150 pmol L-1 and. The applicability of the aptasensor is measured by its successful use in the sensing BPA in water, milk and juice samples and measuring BPA migration from different commercial plastic products.

Automated summary

The research utilized anti-BPA aptamer functionalized gold electrode and magnetic Fe3O4/Au nanoparticles for the detection and analysis of BPA, successfully measuring the content of BPA in water, milk, juice samples, as well as the migration of BPA from different commercial plastic products.