Cefdinir

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.

Cefdinir (Cef) is an orally active Biopharmaceutics Classification System (BCS) class IV drug with incomplete absorption and low bioavailability (16-21%). The aim of this investigation was to develop nanosuspensions (NS) of Cef to improve its oral bioavailability. Cef NS were prepared by the media milling technique using zirconium oxide beads as the milling media. Cef NS were characterized by particle size, Scanning Electron Microscopy, Differential Scanning Calorimetry, X-Ray Diffraction pattern and evaluated for saturation solubility, in vitro release studies, ex vivo permeability studies and in vivo bioavailability studies. The particle size and zeta potential were found to be 224.2 ± 2.7 nm and -15.7 ± 1.9 mV, respectively. Saturation solubility of NS was found to be 1985.3 ± 10.2 µg/ml which was 5.64 times higher than pure drug (352.2 ± 6.5 µg/ml). The DSC thermograms and XRD patterns indicated that there was no interaction between drug and excipients and that the crystallinity of Cef remained unchanged after media milling process.