Improved dissolution rate of oxcarbazepine by centrifugal spinning: in-vitro, in-vivo implications

Low dissolution rates of poorly soluble drugs are the problem afflicting their bioavailability. The aim of this study is to prepare centrifugal spinning based formulation of a poorly soluble drug, oxcarbazepine for the improvement of dissolution rate and hence quick action. Sucrose based microfibers of oxcarbazepine were prepared by centrifugal melt spinning technique using a cotton candy machine. The prepared microfibers were characterized using SEM, PXRD, DSC and FTIR. The optimum formulation was molded into tablets and tested for in-vitro drug release and in-vivo pharmacokinetic studies using rabbits as test animals. The results indicated that the centrifugal spinning has produced rapidly dissolving microfibers (diameter ranges <10 µm and dissolve in few seconds). In these fibers ~20% oxcarbazepine was loaded, and both the yield and drug loading efficiency were improved by incorporating PVP in the formulations. The dissolution studies have revealed > 90% of drug was dissolved in just 2 minutes as compared with drug alone that shows only 15% dissolution at this time interval. XRD and DSC analysis have shown amorphous state of drug in the fibers while FTIR study have shown chemical stability of oxcarbazepine in the fibers. In-vivo studies have revealed a 1hr reduction in t_max of drug in the rabbits treated with microfibers as compared with controlled group which was given pure oxcarbazepine. The study concludes the potential of centrifugal spinning technique for the production of drug loaded fibers that can significantly enhance the dissolution rates of poorly soluble drugs and thus produce formulations for quick action of such drugs. Furthermore, the sucrose based formulation can enhance the palatability with the intend to attract pediatric patients.