Voltammetric determination of glycopyrrolate in a pharmaceutical formulation

Abstract

The electrochemical activity of glycopyrrolate was studied. Different voltammetric techniques were applied in 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 reversible redox reaction on the working electrode surface, with an anodic peak current at approximately 1.05 V and a cathodic peak at 0.80 V. Several parameters that affect the sensitivity of these methods were optimized for the quantitation of glycopyrrolate. LSV showed a better correlation coefficient than DPV did, with a value of ca. 0.9990 in the range of 0.1-0.5 mg/mL. The LSV and DPV recovery and relative standard deviation (RSD) results fell within the accepted range, 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.