Preconcentration and spectrophotometric determination of oxymetholone in the presence of its main metabolite (mestanolone) using modified maghemite nanoparticles in urine sample

A novel and sensitive extraction procedure using maghemite nanoparticles (gamma-Fe2O3) modified with sodium dodecyl sulfate (SDS), as an efficient solid phase, was developed for removal, preconcentration and spectrophotometric determination of trace amounts of oxymetholone (OXM), in the presence of mestanolone (MSL). Combination of nanoparticle adsorption and easily magnetic separation was used for the extraction and desorption of OXM. The preparation of gamma-Fe2O3 nanoparticles were obtained by co-precipitation method and their surfaces were modified by SDS. The size and properties of the produced gamma-Fe2O3 nanoparticles were determined by X-ray diffraction analysis, FT-IR and scanning electron microscopy measurements. OXM and MSL became adsorbed at pH 3.0. The adsorbed drugs were then desorbed and determined spectrophotometrically using a selective complexation reaction for OXM. The calibration graph was linear in the range 15.0-3300.0 ng mL(-1) of OXM with a correlation coefficient of 0.9948. The detection limit of the method for determination of OXM was 4.0 ng mL(-1). The method was applied for the determination of OXM in human urine samples. (C) 2013 Elsevier B.V. All rights reserved.