Gold Nanoparticles-Modified Screen-Printed Carbon Electrode for Voltammetric Determination of Sildenafil Citrate (Viagra) in Pure Form, Biological and Pharmaceutical Formulations

摘要

In this work, a highly sensitive electrochemical sensor for the determination of sildenafil citrate (SILC)drug (the active component of Viagra) was fabricated by electrodeposition of gold nanoparticles(AuNPs) onto a screen-printed glassy carbon electrode (SPGCE). Cyclic voltammetry (CV) and Squarewave voltammetry (SWV) were used to characterize the redox behavior of SILC in absence andpresence of AuNPs. The response of the SPGCE electrode for SILC determination was observed to beenhanced in presence of AuNPs. The peak currents for SILC at AuNPs/SPGCE show a linear response -1 in the concentration range from 1.810 to 3.310 mol L with good reproducibility. The limit of-10 -1 detection was found to be 5.210 mol L .An interference study was also carried out in presence ofhigh concentration of ascorbic acid (AA), and uric acid (UA) to estimate the high selectivity of theelectrode. The modified sensor was successfully applied for the determination of SILC in simulatedhuman urine samples and pharmaceutical formulation with good agreement between the added andrecovery values.