Abstract: In this study, a molecularly imprinted electrochemical sensor based on graphene/Au nanoparticles (G@AuNPs) compound materials and molecularly imprinted membrane (MIM) modified glassy carbon electrodes (GCEs) was developed for the sensitive detection of colchicine in pharmaceuticals and serum (MIM/G@AuNPs/GCE). The film was formed by the in situ polymerization of colchicine-imprinted membranes on the G@AuNPs-modified GCE using methacrylic acid as the functional monomer. The specific surface area, catalytic performance, and electrical conductivity of the electrode increased on account of the formation of G@AuNPs compound materials, thereby improving the sensitivity of the sensor. The MIM as a preconcentrator exhibited chemical selectivity. Under optimal conditions, the MIM/G@AuNPs/GCE sensor exhibited high selectivity and high anti-interference ability. Moreover, good linearity was obtained in the range of 1.2 x 10-8 to 1.2 x 10-6 mol L-1 and 1.2 x 10-6 to 1.0 x 10-4 mol L-1 of colchicine with a detection limit of 4.8 x 10-9 mol L-1. The sensor was successfully applied for the direct determination of colchicine in colchicine tablets and human serum samples, with a relative standard deviation of less than 3.1% (n = 5) and recoveries ranging from 97.5% to 110.0%
Author keywords: Colchicine, molecularly imprinted membrane, AuNPs, Graphene