Voltammetric determination of glycopyrrolate in a pharmaceutical formulation

Abstract

The electrochemical activity of glycopyrrolate was studied. Different voltammetric techniques were appliedin this study, including cyclic voltammetry (CV), differential pulse voltammetry (DPV), and linear sweep voltammetry(LSV). Glassy carbon and platinum working electrodes were utilized. CV indicated that glycopyrrolate has a reversibleredox reaction on the working electrode surface, with an anodic peak current at approximately 1.05 V and a cathodicpeak at 0.80 V. Several parameters that affect the sensitivity of these methods were optimized for the quantitation ofglycopyrrolate. LSV showed a better correlation coefficient than DPV did, with a value of ca. 0.9990 in the range of0.1–0.5 mg/mL. The LSV and DPV recovery and relative standard deviation (RSD) results fell within the acceptedrange, with a better recovery (102.07%) for DPV and a better RSD (0.511%) for LSV. The limits of detections were ca.16 and ca. 25 µg/mL for LSV and DPV, respectively.