The Simultaneous Determination of Ascorbic Acid, Paracetamol, and Caffeine by Voltammetry Method Using Cobalt Schiff Base Complex/SBA-15 Modified Electrode

Abstract

In this work, the synthesis of cobalt Schiff base complex embedded SBA-15 and simultaneous determination of ascorbic acid (ASA), paracetamol (PAR), caffeine (CAF) by square anodic stripping voltammetry (SqW-ASV) are performed. The cobalt Schiff base complex has been derived from salicylaldehyde, 3(-aminopropyl) triethoxysilane, and cobalt acetate. Cobalt Schiff base complex embedded SBA-15 materials was synthesized via anchoring cobalt Schiff base complex on mesoporous SBA-15. Due to the synergetic effects from the cobalt Schiff base complex (excellent electrochemical properties) and SBA-15 (stable and large surface area) the oxidation peak currents of ASA, PAR and CAF on the modified glassy carbon electrode (GCE) are much higher than those on the Schiff base complex/GCE and bare GCE. The modified electrode exhibited an effective catalytic response to the oxidation of ASA, PAR, and CAF with good reproducibility and stability. The modified GCE has a detection limit of 0.085 μM for ASA, 0.059 μM for PAR and 0.032 μM for CAF. The proposed SqW-ASV method was successfully applied in the simultaneous determination of ASA, PAR and CAF in several pharmaceutical preparations, with results similar to those obtained by high-performance liquid chromatography.