Functionalized metal oxide nanoparticles based electrochemical sensors for the detection and quantification of pharmaceuticals

Abstract

Metal oxide nanoparticles (MONPs) are of high significance in sensing as they provide newlineviable solutions to the enduring challenges related to lower detection limits. Integration of MONPs in electrochemical sensors makes them an innovative element in pharmaceutical assays. MONPs-based electrochemical sensors have gained a paramount of attention towards pharmaceutical application owing to its selectivity towards the analyte, sensitivity, high stability and simplicity of preparative techniques. Therefore, MONPs are used for the newlineelectrochemical determination of pharmaceutical drugs on glassy carbon electrode (GCE) that functions as transducer host. Template assisted synthesis and hydrothermal synthesis of MONPs has resulted in the formation self-assembled nanospheres which have further contributed to the efficiency of the sensor. Further, surface functionalization of MONPs and synthesis of MONPs-nanocomposite have remarkably decreased the aggregation of MONPs and enhanced the efficiency of the electrochemical sensor. Different characterizations like X-ray diffraction, fourier transform infrared spectroscopy, dynamic light scattering, scanning electron microscopy, high resolution transmission electron microscopy, vibrating sample magnetometry were carried out to study various properties of the synthesized MONPs. The synthesized MONPs were drop casted on to the GCE for the determination of pharmaceutical samples. The modified GCEs were electrochemically characterized using electrochemical impedance spectroscopy. The Nyquist plots displayed low charge transfer resistance with improved surface area. Various experimental parameters required for the effective electrochemical sensing such as electrolyte pH, scan rate, concentration of analyte and potential window were optimized with extreme care. Differential pulse voltammetry was used to validate the proposed electrochemical sensors with micro to nano level detection limits with a wide linear range and remarkable sensitivity.