A photoelectrochemical immunosensor based on Z-scheme CdS composite heterojunction for aflatoxin B1

Fubin Pei; Shasha Feng; Yuehua Zhang; Yi Wu; Chenglong Chen; Yue Sun; Zihao Xie; Qingli Hao; Yang Cao; Zhaoyang Tong; Wu Lei

doi:10.1016/j.bios.2022.114500

A photoelectrochemical immunosensor based on Z-scheme CdS composite heterojunction for aflatoxin B1

Biosens Bioelectron. 2022 Oct 15:214:114500. doi: 10.1016/j.bios.2022.114500. Epub 2022 Jun 24.

Authors

Fubin Pei¹, Shasha Feng¹, Yuehua Zhang², Yi Wu¹, Chenglong Chen¹, Yue Sun¹, Zihao Xie¹, Qingli Hao¹, Yang Cao¹, Zhaoyang Tong³, Wu Lei⁴

Affiliations

¹ School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, Jiangsu, China.
² School of Chemistry and Chemical Engineering, Nantong University, Nantong, 226019, China.
³ State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, China. Electronic address: billzytong@126.com.
⁴ School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, Jiangsu, China. Electronic address: leiwuhao@njust.edu.cn.

PMID: 35797936
DOI: 10.1016/j.bios.2022.114500

Abstract

Aflatoxin B1 (AFB1) is a highly toxic fungal contaminant widely found in agricultural products. It causes serious harm to human health and the environment. Thus, a fast and sensitive detection approach is urgently needed to prevent AFB1-contaminated products from entering the market effectively. A photoelectrochemical (PEC) immunosensor was developed based on tungsten trioxide/cadmium sulfide core/shell coated with a composite layer consisting of polydopamine and loaded gold nanoparticles (WO₃/CdS@PDA/Au) for AFB1 detection. CdS formed a heterojunction with WO₃, which improved the photoelectric performance. The coated PDA reducing CdS toxicity was demonstrated by biological experiment of Bacillus subtilis. PDA and Au NPs promoted electron transfer between the semiconductors, being beneficial promoting the photoelectron transfer. Additionally, the antibodies were immobilized on WO₃/CdS@PDA/Au via the reactive quinones on the surface of the PDA and electrostatic adsorption from Au NPs. The WO₃/CdS@PDA/Au composite as a Z-scheme heterojunction possessed high performance of photocurrent response, and the photoproduced electron/hole transfer path was speculated by electrons spin-resonance spectroscopy technique. Under the optimum experimental conditions, the PEC immunosensor showed a wide linear detection range from 0.05 to 100 ng mL^-1 for AFB1, indicating that the immunosensor has a bright application prospect.

Keywords: Aflatoxin B1; Photoelectrochemical immunosensor; WO(3)/CdS@PDA/Au; Z-Scheme heterojunction.

MeSH terms

Aflatoxin B1
Biosensing Techniques* / methods
Electrochemical Techniques / methods
Gold / chemistry
Humans
Immunoassay / methods
Limit of Detection
Metal Nanoparticles* / chemistry

Substances

Gold
Aflatoxin B1