Electrochemical Sensor Based on Nanocomposite of Ionic Liquid Modified Graphene Oxide – Chitosan and its Application for Flow Injection Detection of Anticancer Thiopurine Drugs

Abstract

Abstract Electrochemical activity of carbositall electrodes (CSEs) covered with polymeric films of Chitosan (Chit) containing different types of graphene oxide (GO) dispersed in a room temperature ionic liquid (IL) was comparatively investigated by using cyclic voltammetry of [Fe(CN) 6 ] 3−/4− as a model redox probe. It was recognized that the nanocomposite film with in situ electrochemically reduced GO (ERGO) provided an improved electrochemical activity, including increased peak current and electron‐transfer efficiency, compared to the initial GO nanosheets and chemically reduced GO (RGO). The novel electrochemical sensor ERGO‐IL‐Chit/CSE showed enhanced electrochemical response characteristics towards the antimetabolic thiopurines such as 6‐thioguanine, 6‐mercaptopurine and azathioprine which play a significant role in medicinal chemistry and cancer therapy. The diagnostic characteristics of the voltammetric signals for all investigated compounds in neutral aqueous media were established and the nature of the corresponding redox‐reactions was discussed. The developed sensor was incorporated into a flow injection amperometric system for the automatic dissolution testing of thiopurine anticancer drugs with a sampling rate of 60 h −1 .