Determination of deferasirox in human plasma by short-end injection and sweeping with a field-amplified sample stacking and micellar electrokinetic chromatography

A field-amplified sample stacking-sweeping micellar electrokinetic chromatography with short-end injection was established for determination of deferasirox (DFX) in plasma. DFX was extracted from plasma and reconstituted with deionized water (lower conductivity solution). Capillary (effective length, 10 cm) was filled with background electrolyte (40 mM phosphate buffer, pH 4.5, containing 20% methanol). After sample loading from outlet end at 5 psi for 15 s, separation was carried out by applying high voltage at 15 kV for 10 min. Sodium dodecyl sulfate (SDS) was used to sweep DFX for enhancing sensitivity. The optimal CE separation conditions were 40 mM phosphate buffer at pH 4.5 containing 100 mM SDS and 20% methanol. The analysis time was about 3.5 min for DFX. The calibration curve of DFX was ranged from 1 to 20 mu g/ml. The linearity (r) was more than 0.998. RSD and RE in intra- and inter-day assays were all below 12.14%. The limit of detection (LOD, S/N = 3) for DFX was 0.31 mu g/ml. The sensitivity enhancement factor between sweeping-FASS MEKC and capillary zone electrophoresis is 3.3. Finally, the method was applied for determination of DFX in beta-thalassemia patients. (C) 2016 Elsevier B.V. All rights reserved.