Determination aminopyrine in pharmaceutical formulations based on APTS-Fe3O4 nanoparticles modified glassy carbon electrode

In this work, 3-aminopropyltriethoxysilane modified Fe3O4 nanoparticles (ATPS-Fe3O4) were used to modify glassy carbon electrode for aminopyrine determination. ATPS-Fe3O4 showed obviously catalytic activity and adsorptivity towards aminopyrine oxidation proven by the increased oxidation peak current and the decreased oxidation peak potential. The best analytical response was obtained by immobilizing 8 mu L 3 mg/mL APTS-Fe3O4 dispersion with an accumulation time of 200 s at -0.2 V in 0.1 M phosphate buffer solution (pH 9.0). The oxidation peak current of aminopyrine showed linear relationship with its concentration in the range from 0.5 to 100 and 100 to 1600 mu M. The detection limit was 0.1 mu M (S/N= 3). The proposed method showed satisfactory repeatability and anti-interference ability. The fabricated electrode was successfully applied to determine aminopyrine in pharmaceutical formulations.