Synchronous analysis of acetaminophen, codeine, and caffeine in human fluids employing graphite screen-printed electrodes

Abstract

A facile electrochemical approach is proposed for the synchronous determination of acetaminophen (ACP), codeine (COD) and caffeine (CAF) utilizing unmodified screen-printed electrodes (SPEs). The determination of ACP, COD and CAF has been explored across different supporting electrolytes including sulfuric acid (H₂SO₄), hydrochloric acid (HCl), phosphoric acid (H₃PO₄) and Briton Robinson (B.R) buffer solutions. It was found that a 0.05 mol L⁻¹ sulfuric acid solution is an optimal supporting electrolyte utilized for voltammetric analysis of ACP, COD, and CAF with improved sensitivity, stability, and reproducibility. The electro-analytical sensing of ACP, COD and CAF was investigated using SPEs within linear concentration ranges of 3.0–35.0 μmol L⁻¹, 10–160 μmol L⁻¹ and 10–160 μmol L⁻¹ and revealed competitively low limits of detection (3S/N) of 0.9, 4.8 and 6.3 μmol L⁻¹ for ACP, COD and CAF, respectively. The results indicated the possibility of such a simple and quick electroanalytical protocol for online monitoring of pharmaceutical formulations comprising ACP, COD, and CAF drugs in human fluids with satisfactory recovery.