Powerful Analytical Platform for Diazepam Determination in Pharmaceuticals and Alcoholic Drinks Based on Batch Injection Analysis Coupled with Adsorptive Stripping Voltammetry

• Published in: Journal of the Electrochemical Society Vol. 171; no. 4; pp. 47517 - 47526
• Main Authors: Haššo, Marek, Kekeľáková, Adela, Hanko, Michal, Švorc, Ľubomír
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.04.2024
• Subjects: analysis of alcoholic drink; batch injection analysis; diazepam; pharmaceutical analysis; square-wave adsorptive stripping voltammetry
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1945-7111/ad3c95

The presented study focuses on the development and optimization of a powerful electroanalytical platform for the direct quantification of diazepam (DZP). This innovative approach integrates a batch injection analysis (BIA) system with a screen-printed electrode arrangement employing square-wave adsorptive stripping voltammetry (SWAdSV). The BIA-SWAdSV method underwent a comprehensive evaluation, wherein various experimental and instrumental parameters were systematically examined in detail. Beneficial analytical performance for detecting DZP was attained in Britton-Robinson buffer with pH 6.0, with an amplitude of 75 mV, a frequency of 10 Hz, a deposition potential of –1.2 V, a deposition time of 150 s, an injection volume of 75 μ l, a dispensing rate of 7 μ l s −1 and without stirring during the deposition step. Under these conditions, the proposed BIA-SWAdSV method demonstrated an adequately broad linear concentration range from 5 μ M to 40 μ M ( R 2  = 0.997) with a micromolar limit of detection (2.0 μ M) and a satisfactory precision (RSD = 5.0%). The practical applicability of the newly established and powerful analytical protocol was confirmed through the analysis of pharmaceuticals and a fortified samples of an alcoholic drink (rum) associated with potential criminal activities involving DZP abuse.