One-step electrodeposition of a molecularly imprinting chitosan/phenyltrimethoxysilane/AuNPs hybrid film and its application in the selective determination of p-nitrophenol

This paper presents the fabrication of a molecularly imprinting sol-gel hybrid film by the one-step electrodeposition of the constitutional individuals including chitosan (CS), phenyltrimethoxysilane (PTMS), in situ formed gold nanoparticles (AuNPs) and template p-nitrophenol (p-NP). The electrodeposition was triggered by applying an optimal potential at -0.30 V vs. SCE, leading to the formation of the p-NP imprinting CS/PTMS/AuNPs hybrid film on a glassy carbon electrode (GCE) with a roughly architectural and conductive nature, as revealed by scanning electron microscopy and electrochemical impedance analysis. The mechanism of the hybrid film formation was discussed accordingly. Upon complete removal of the template molecules assisted by cyclic voltammetry, the p-NP imprinted film modified electrode exhibited differential pulse voltammetric (DPV) responses to p-NP in a linear range from 3.0 x 10(-8) to 3.5 x 10(-4) M with a detection limit of 5.0 x 10(-9) M. The selectivity and reusability of the sensor was demonstrated by discriminating the p-NP response from its analogues and successive rebinding/debinding cycles, respectively. The methodology is extendable as a simple and general platform for developing hybrid film sensors for the specific determination of various electrochemically active species.