In this study, an organic-inorganic hybrid monolithic capillary column was applied and optimized for the determination of cefdinir in plasma, and the electro-osmotic flow that usually hinders migration in reverse polarity became a driving force. The Sample used for pharmacokinetic research was collected by microdialysis using phosphate buffer (pH 7.4) as perfusate, and a volume of 60 μL fluid was mixed with 140 μL of acetonitrile. By using a silica-allyldimethyldodecylammonium monolithic column (100 μm inner diameter, 21 cm effective length and 31.2 cm total length), and a mobile phase consisting of phosphate and acetonitrile (pH 4.5, 50:50, v/v), at a voltage of 20 kV, the analytes were successfully separated with the background within 2.5 min. The detection wavelength was 214 nm. The calibration curve showed a good linearity (r(2) = 0.9994) over the concentration range of 0.2-50 μg/mL. The proposed method showed good specificity, linearity, sensitivity, precision and recovery, and the introduction of field amplified sample stacking helped to improve the low recovery caused by microdialysis. This method was successfully applied to quantify cefdinir in rat plasma to support a pre-clinical pharmacokinetic trial.
Keywords: Capillary electrochromatography; Cefdinir; Hybrid monolithic columns; Microdialysis.
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.