Simultaneous determination of caffeine, paracetamol, and ibuprofen in pharmaceutical formulations by high‐performance liquid chromatography with UV detection and by capillary electrophoresis with conductivity detection

Abstract

Paracetamol, caffeine and ibuprofen are found in over-the-counter pharmaceutical formulations. In this work, we propose two new methods for simultaneous determination of paracetamol, caffeine and ibuprofen in pharmaceutical formulations. One method is based on high-performance liquid chromatography with diode-array detection and the other on capillary electrophoresis with capacitively coupled contactless conductivity detection. The separation by high-performance liquid chromatography with diode-array detection was achieved on a C18 column (250×4.6 mm(2), 5 μm) with a gradient mobile phase comprising 20-100% acetonitrile in 40 mmol L(-1) phosphate buffer pH 7.0. The separation by capillary electrophoresis with capacitively coupled contactless conductivity detection was achieved on a fused-silica capillary (40 cm length, 50 μm i.d.) using 10 mmol L(-1) 3,4-dimethoxycinnamate and 10 mmol L(-1) β-alanine with pH adjustment to 10.4 with lithium hydroxide as background electrolyte. The determination of all three pharmaceuticals was carried out in 9.6 min by liquid chromatography and in 2.2 min by capillary electrophoresis. Detection limits for caffeine, paracetamol and ibuprofen were 4.4, 0.7, and 3.4 μmol L(-1) by liquid chromatography and 39, 32, and 49 μmol L(-1) by capillary electrophoresis, respectively. Recovery values for spiked samples were between 92-107% for both proposed methods.

Evaluation of sample injection precision in respect to sensitivity in capillary electrophoresis using various injection modes

“…Based on the results presented in Table 1, it can be noted that HPLC featured the greatest injection repeatability among the tested techniques. The results obtained for HPLC and CE with standard hydrodynamic injection are comparable with the precision obtained by Cunha et al in a similar study [21]. The CV values obtained for each analyte were schematically juxtaposed against the tested concentration levels in the Supporting Information.…”

Capillary electrophoresis with capacitively coupled contactless conductivity detection method development and validation for the determination of azithromycin, clarithromycin, and clindamycin

“…CE with capacitively coupled contactless conductivity detection (C 4 D) offers a compact and simple system for pharmaceutical analysis. CE works on the principle of differential migration of ionic species while the detector unit measures the conductivity difference between the sample band and the BGE . This set‐up with considerable automation requires very low sample and solvent consumption.…”

Application of capillary electrophoresis with capacitively coupled contactless conductivity detection (CE‐C4D): An update

“…A fast method for the simultaneous determination of caffeine, paracetamol and ibuprofen in pharmaceutical formulation was demonstrated (Cunha et al, ). The separation of the three analytes was achieved in 2.2 min, as presented in Figure , using a fused‐silica capillary (40 cm length, 50 μm i.d.)…”