A highly-sensitive VB2 electrochemical sensor based on one-step co-electrodeposited molecularly imprinted WS2-PEDOT film supported on graphene oxide-SWCNTs nanocomposite

Abstract

A highly-sensitive electrochemical sensor based on single walled carbon nanotubes (SWCNTs) nanocomposite electro-catalyst supported molecularly imprinted poly(3,4-ethylenedioxythiophene) (PEDOT) film modified with two-dimensional layered tungsten sulfide (WS2) nanosheet for the detection of vitamin B2 (VB2) was successfully developed. Molecularly imprinted WS2-PEDOT film was prepared by the electrochemical co-polymerization of functional monomer 3,4-ethylenedioxythiophene in the presence of template molecule VB2 and WS2 nanosheet. SWCNTs nanocomposite modified electrode was obtained by drop-coating SWCNTs dispersion containing graphene oxide (GO) onto GCE surface. WS2 was used for improving the denseness and smoothness in the morphology and structure of PEDOT. GO was employed for enhancing the electro-catalytic capacity of SWCNTs and the interaction with template molecule via functional groups. The imprinted sensor was characterized, and its performance and parameters were investigated and optimized using linear sweep voltammetry. Under optimized conditions, the prepared imprinted sensor displayed a good linear response to VB2 in wide concentration ranges from 0.002 to 0.9 μM with a low detection limit of 0.7 nM, and successfully applied to electrochemically detect VB2 in drug samples with good reproducibility, repeatability and storage stability. The new design for the facile fabrication of mimic electrode will open up a new horizon in the development of highly-sensitive biomimic/imprinted sensors.