Determination of indacaterol from inhaler capsules by square-wave voltammetry at the surface of the boron-doped diamond electrode
Hemn A.H. Barzani, Hoshyar Saadi Ali, Yavuz Yardım
Abstract
This research paper presents an electroanalytical investigation using the voltammetric method to quantify indacaterol maleate (IND) employing an unmodified boron-doped diamond (BDD) electrode. IND exhibited a distinct, irreversible oxidation peak at approximately 1.06 V (vs. Ag/AgCl) in a 0.1 mol L-1 phosphate buffer solution (PBS) with a pH of 2.5, as demonstrated by cyclic voltammetry (CV). A hypothetical mechanism for the electro-oxidation of IND, based on data gathered from CV investigations, was suggested. The square wave-adsorptive stripping voltammetric technique achieved acceptable linearity in PBS (pH 2.5) at approximately 0.90 V. The methodology demonstrated linearity within the concentration range of 1.0 to 30.0 ?g mL-1 (equivalent to 1.97?10-6?5.89?10-5 mol L-1) and yielded a limit of detection (LOD) of 0.22 ?g mL-1 (equivalent to 4.33?10-7 mol L-1). The proposed method?s applicability was assessed through the sensing of IND in drug formulations.