Determination of pyridoxine (vitamin B6) in pharmaceuticals and urine samples using unmodified boron-doped diamond electrode

Pyridoxine (vitamin B-6, VB6) was detected in pharmaceutical preparation and human urine samples by employing differential pulse voltammetry (DPV) at unmodified boron doped electrode. In Britton-Robinson buffer solution (BRBS) at pH 6, VB6 provides well defined oxidation peak at around +1.05 V vs. Ag/AgCl (3 M KCl). The influence of most of the interferents present in real samples, supporting electrolyte and DPV parameters was investigated. A VB6 sensor with and linear range from 7 to 47 and a detection limit of 3.76 was obtain after optimization. Repeatability of the proposed procedure calculated after 7 measurements of 9 and 30 mu M of VB6 was 3.6 and 2.4%, respectively. Proposed methodology was successfully applied for the determination of VB6 in real samples, and from obtained results, it can be concluded that proposed analytical procedure can be an inexpensive alternative to the widely used separation methods. Prime Novelty statement: This work presents the quantification of vitamin B-6, using differential pulse voltammetry, with boron-doped diamond electrode. BDD electrode is, up to date, one of the best electrode materials, with extremely low background current and negligible passivation. The aim of this study was to develop method for vitamin B-6 determination in various matrices, as can be seen from the results, the obtained procedure shows good recovery values in tested samples and could be a satisfactory replacement to the separation methods and modified electrodes. (C) 2016 Elsevier B.V. All rights reserved.