Clinical Application Study of Polymeric Nanospheres Network in Methylphenidate Extraction from Urine Samples by...

This research introduces a polymeric nanosphere as a new dispersive solid phase extraction (DSPE) adsorbent for the extraction of methylphenidate (MPH) from urine and its high performance liquid chromatography (HPLC) analysis. Polymeric nanosphere is a kind of copolymeric network obtained by copolymerization of an ionic liquid monomer and styrene in the presence of vinyltriethoxysilane and 2-hydroxyethylmethacrylate. HPLC coupled with ultra violet detector was applied for the determination and quantification of MPH. Dominant parameters in extraction were modified by the one-parameter-at-a-time method. The results are as follow: 10 mg of polymeric nanospheres (PNS), 400 μL of acetonitrile (ACT), 5 mL of urine with the pH value of 9, and the extraction and desorption times of 2 and 5 minutes, respectively, which can be selected as the optimum extraction conditions. Calibration curve was plotted through optimized conditions, and the proposed method was validated. The results demonstrated that the method presented linearity in the concentration range of 30-1200 ng/mL. Selectivity, matrix effect and metabolites interference effect were investigated and the method presented no obvious interference effect during the analysis run time. Repeatability, limit of detection (LOD) and limit of quantification (LOQ) values of the method can be reported in this section as well. The method showed satisfactory results with 98.8% relative recovery in the analysis of positive urine samples. The findings convinced the applicability of the introduced method for DSPE and HPLC analysis of the positive urine samples in different laboratories.