Construction of nanoparticles composite sensor for atorvastatin and its determination in pharmaceutical and urine samples

In the present work, first time a composite electrode based on nano-silica and zinc oxide nanoparticles were investigated for electrochemical determination of atorvastatin. The electrochemical behavior of atorvastatin at carbon paste electrode, initially modified with nano-silica was investigated. Further, the effect of addition of ZnO nanoparticles toward the electrochemical behavior of atorvastatin was studied and both were compared. The cyclic voltammetric peak current had a significant enhancement at nano-silica modified electrode as compared with the bare electrode. With addition of ZnO nanoparticles, it was observed that there was a large enhancement in the peak current as compared to that of nano-silica modified electrode. Parameters such as number of electrons transferred, diffusion coefficient, and heterogeneous rate constant were calculated. Limit of detection and quantification was calculated under the optimized conditions. For the analytical applications, pharmaceutical dose form and human urine sample analysis were performed. Various interferents were used to investigate the interference in the analytical application and was found that the proposed method would be well adopted for clinical trials and real sample analysis.