Challenging electroanalytical method for the determination of mirabegron in biological samples and pharmaceutical formulations

A simple, economic, sensitive, and time-saving differential pulse voltammetric (DPV) procedure using nanostructured zinc oxide modified carbon paste electrode (nano ZnO-CPE) in conjunction with an anionic surfactant sodium dodecyl sulfate (SDS) was developed for ultra- sensitive detection of mirabegron (MIR), the most prescribed pharmaceutical drug in treatment of overactive bladder (OAB). The use of nanostructured zinc oxide CPE modifier increased the electrode active surface area as well as improved the process of electron transfer, also it was found that at optimal conditions MIR electrochemical process was both irreversible and diffusion-regulated. The morphological characterization of the fabricated electrode was performed using field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectroscopy (EDX). MIR voltammetric behavior was investigated using Nano ZnO-CPE in different content and electrode compositions. Therefore, ultra-sensitive results were attained with a linearity range of (0.55 to 100.20 ng ml-1) and a low limit of detection (LOD) of 0.51 ng ml-1 and limit of quantification (LOQ) of 1.54 ng ml-1 in a 0.04 M Britton-Robinson (BR) buffer at an adjusted pH of 6.0 with scan rate 100 mV s-1. Furthermore, the proposed approach was successful in measuring MIR with acceptable percentage recoveries (99.81-100.11 %) in pharmaceutical dosage form and varying concentration ranges in biological samples (99.74-100.35 %). The proposed method has been validated using ICH criteria and proven to be accurate and repeatable.