Molecularly Imprinted Polymer (MIP) Electrochemical Sensor based on Graphene Modified Platinum Electrode for Sertraline Determination

Abstract

In this report, a new electrochemical sensor was developed for sertraline (STR) analysis. The sensor was prepared based on modified Pt electrode with graphene nanoparticles and molecular imprinting polymer (MIP) by coating a very thin layer of polymer onto a support. Through this approach, all of the binding sites of the polymer immobilized on the electrode surface are available for target molecules. The STR binding experiments indicated that the sensor modified by MIP have much higher adsorption ability than non−imprinted polymer (NIP) based sensor. Also, using of graphene in preparation of Pt electrode leads to a significant improvement in response of electrode because of their high electrical conductivity and large surface areas as the platform of the polymer that makes the graphene-MIP an excellent electrical transducer for direct electrical sensing. The cyclic voltammetry (CV) and differential pulse voltammetry (DPV) tests were used to evaluate the performance of the electrochemical sensor. Some parameters affecting the sensor performance such as MIP suspension, extraction pH and preconcentration time were optimized and under optimal conditions, the modified sensor with MIP-graphene showed linear responses with STR concentration in the range of 1.0×10-8 to 1.0×10-6 mol L-1 (R2 = 0.985) with a detection limit of 7.0×10-9 mol L-1. This developed sensor with the MIP was consequently capable of selective sensing of STR in human serum sample with recovery values in the range of 98.2-103.5%.