Molybdenum (IV) Sulfide Nanosheet-Based Aptasensor for the Label-Free Determination of Bisphenol A (BPA) by Electrochemical Impedance Spectroscopy (EIS)

Abstract

Simple and accurate detection of bisphenol A (BPA) is important for environmental monitoring and food safety. Herein, a MoS₂-based electrochemical aptasensor was designed for label-free BPA detection based on the different affinities of MoS₂ nanosheets toward single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA). The specific interaction between BPA and an anti-BPA aptamer forms a BPA-aptamer complex, which is released from the MoS₂ film modified electrode surface due to the change of aptamer configuration. Correspondingly, the electrochemical impedance of the modified electrode was reduced with the decrease in the loaded aptamer concentration. The aptasensor determined from 1 nM to 10 µM BPA with a detection limit of 0.33 nM. The high sensitivity, selectivity, and reproducibility of this aptasensor allows the determination BPA in artificial and real samples with satisfactory results.

Keywords:

• Bisphenol A
• electrochemical impedance spectroscopic (EIS)
• molybdenum (IV) sulfide nanosheet
• double-stranded DNA (dsDNA)
• single-stranded DNA (ssDNA)

Additional information

Funding

This project was supported by the Fundamental Research Funds for the Provincial Universities, Zhejiang Institute of Economics and Trade (Grant Number: 21SBYB03).