Tóm tắt

A novel sensor prepared by mixing nanosilica and graphite powder in an appropriate ratio for the deter-mination of nimesulide drug to study its electrochemical response. Nanosilica showed good conductivityrnin the transfer of the electrons involved in the oxidation process. The homogeneous mixing of graphiternpowder with nanosilica has a good response time, stability, sensitivity, and reproducibility. A remarkablernincrease in the oxidation peak current was observed in phosphate buffer solution (PBS). Effect of accumu-lation time, scan rate, pH, concentration, excipients, and metal ions on the voltammetric behavior of therndrug was studied by various voltammetric techniques. The catalytic properties of nanosilica particlesrnreveal an increase in the peak current with a less negative value of the potential. The relationshiprnbetween scan rate and peak potential direct to calculate a number of electrons and protons involvedrnin the electro-oxidation process. A linear plot was obtained by varying the concentrations of the drug.rnA low detection limit value and good recovery values show us the applicability of the proposed electrodernfor pharmaceutical and urine samples analysis