A novel ratiometric electrochemical sensor based on dual-monomer molecularly imprinted polymer and Pt/Co3O4 for sensitive detection of chlorpromazine hydrochloride

Abstract In this work, a novel signal on/off ratiometric electrochemical sensor for the selective detection of chlorpromazine (CPZ) was developed. The sensor was constructed by electrodepositing dual-monomer molecularly imprinted polymer (DMMIP) film on the surface of Pt/Co3O4 nanoparticles modified glassy carbon electrode, using CPZ as template molecule, methylene blue and catechol as functional monomers. The copolymerization of two monomers increased the diversity of functional groups for binding template molecules, and enhanced stability. The quantitative detection of CPZ was performed by differential pulse voltammetry, using the peak current of poly (methylene blue) as reference signal and the peak current of CPZ as indicating signal. The results showed that the developed DMMIP sensor not only possessed high selectivity and sensitivity, but also exhibited satisfactory anti-interference ability. Under the optimum conditions, a linear detection range of 0.005–9 μmol L-1 (R2 = 0.9962) was obtained, and the limit of detection was 2.6 nmol L-1. Moreover, the sensor showed good reproducibility and stability toward CPZ detection. It was applied to detect CPZ in serum and pharmaceutical samples, and satisfactory recoveries (ranging from 95.3% to 108.0%) were achieved.