Selective Dispersive Solid Phase Extraction of Sertraline Using Surface Molecularly Imprinted Polymer Grafted on SiO2/Graphene Oxide

A surface molecularly imprinted dispersive solid phase extraction coupled with liquid chromatography–ultraviolet detection is proposed as a selective and fast clean-up technique for the determination of sertraline in biological sample. Surface sertraline-molecular imprinted polymer was grafted and synthesized on the SiO2/graphene oxide surface. Firstly SiO2 was coated on synthesized graphene oxide sheet using sol-gel technique. Prior to polymerization, the vinyl group was incorporated on to the surface of SiO2/graphene oxide to direct selective polymerization on the surface. Methacrylic acid, ethylene glycol dimethacrylate and ethanol were used as mono-mer, cross-linker and progen, respectively. Non-imprinted polymer was also prepared for compar-ing purposes. The properties of the molecular imprinted polymer were characterized using field emission-scanning electron microscopy and Fourier transform infrared spectroscopy methods. The surface molecular imprinted polymer was utilized as an adsorbent of dispersive solid phase extrac-tion for separation and preconcentration of sertraline. The effects of the different parameters influ-encing the extraction efficiency, such as sample pH were investigated and optimized. The specific-ity of the molecular imprinted polymer over the non-imprinted polymer was examined in absence and presence of competitive drugs. Sertraline calibration curve showed linearity in the ranges 1–500 μg L^-1. The limits of detection and quantification under optimized conditions were obtained 0.2 and 0.5 μg L^-1. The within-day and between-day relative standard deviations (n=3) were 4.3 and 7.1%, respectively. Furthermore, the relative recoveries for spiked biological samples were above 92%.