LAUSR

In this work, magnetic nanoparticles (Fe3 O4 ) were prepared by simple co-precipitation method in aqueous medium and then subsequently modified with tetraethyl orthosilicate and 3-aminopropyl triethylenesilane. The properties of particles were characterized by FT-IR, X-Ray diffraction, transmission electron microscopy and scanning electron microscopy and. The SiO2 -NH2 @Fe3 O4 particles were successfully applied to simultaneously enrich and separate of diclofenac from waters, urine and plasma samples. The method, which takes the advantages of both nanoparticle adsorption and magnetic phase separation from the sample solution, could avoid some of the time-consuming experimental procedures related to the traditional solid phase extraction. The main parameters affecting extraction and desorption efficiency such as pH, amount of SiO2 -NH2 @Fe3 O4 , volume of desorption solvent and extraction time were screened. The significant variables were optimized by using central composite design. At optimum conditions values of variables set as pH = 4, 10 mg SiO2 -NH2 @Fe3 O4 , 0.5 mL methanol, and 15 min extraction time and then the extracted DIC were injected to HPLC for analysis. The linear response (r2 >0.9992) was obtained in the range of 0.004-15 μg mL-1 with detection limit 0.0012 μg mL-1 and extraction recovery was in the range of 92-96% with RSD <5.0 % (n = 6). This article is protected by copyright. All rights reserved.