Enhanced photocurrents for photoelectrochemical immunoassay of alpha-fetoprotein with Pt-functionalized Bi2O2S nanoflowers

Anal Chim Acta. 2024 Nov 22:1330:343281. doi: 10.1016/j.aca.2024.343281. Epub 2024 Sep 26.

Abstract

Background: Designing heterojunctions with efficient electron-hole separation holds great promise for improving photoelectric response.

Results: Herein, we reported a multifunctional Pt co-catalyst-modified Bi2O2S nanoflowers (BOS NFs) photocatalytic component for achieving an efficient photoelectric chemistry (PEC) immunosensor for alpha-fetoprotein (AFP). Briefly, the Pt co-catalyst improved the intrinsic band gap structure of BOS on the one hand, and on the other hand, it was able to achieve a rapid decomposition of hydrogen peroxide to hydroxyl radicals, which led to the improvement of electrochemical half-responses during the amplification of target immunosignals. In addition, Pt-functionalized BOS NFs (BOS-Pt) exhibited peroxidase-like enzymatic reaction activity and related properties. By enzyme-linked immunosorbent assay, a sandwich immuno-model in the presence of AFP catalyzed the production of hydrogen peroxide from the substrate glucose and the conversion of a sizable photoelectrochemical signal catalyzed by BOS-Pt. Following condition optimization, it was determined that the developed sensor exhibited a specific response to AFP over a wide linear range of 0.05-50 ng mL-1.

Significance: This work provides a new strategy for developing efficient immunosensors from the perspective of modulating photoelectrochemical half-reactions.

Keywords: Alpha-fetoprotein; Liver cancer; Photocurrent enhancement; Photoelectrochemical immunoassay; Pt-functionalized Bi(2)O(2)S nanoflowers.

MeSH terms

  • Biosensing Techniques / methods
  • Bismuth* / chemistry
  • Catalysis
  • Electrochemical Techniques*
  • Humans
  • Hydrogen Peroxide / chemistry
  • Immunoassay / methods
  • Limit of Detection
  • Nanostructures / chemistry
  • Photochemical Processes*
  • Platinum* / chemistry
  • alpha-Fetoproteins* / analysis

Substances

  • alpha-Fetoproteins
  • Platinum
  • Bismuth
  • Hydrogen Peroxide