Formulation, Development and Evaluation of Floating-Pulsatile Drug Delivery System of Nifedipine.

Research in chronopharmacological field has demonstrated the importance of biological rhythms in drug therapy. Optimal clinical outcome cannot be achieved if drug plasma concentrations are constant. If symptoms of disease display circadian variations drug release should also vary over time. Formulations should be justified by biopharmaceutical and pharmacokinetic study in order to choose the best hour for administration. Another point raised by circadian variation of physiological function is that drug pharmacokinetics can be time-dependent. Variations in physiological and pathophysiological functions in time, also need for variations of drug plasma concentration has brought a new approach to the development of drug delivery systems, chronopharmaceutical drug delivery. The core containing KYRON T-314 disintegrate the tablet within short time due to easy and high swelling ability of KYRON T-314 as compared to CCS The PRT containing the buoyant material, such as HPMC K100M, NaHCO3,and citric acid achieved a satisfactory buoyant force in vitro, whereas the floating onset time was less than 1 min. The pulsatile releasing mechanism of PRT is based on the exploitation of the peculiar interaction between hydrophilic polymeric coating and the aqueous gastrointestinal fluids. The in vitro release profiles of Nifedipine from PRT prepared using HPMC E15LV as retarding polymer are characterized by a predetermined lag time (4.1±0.2 h for K6+F4 ), the duration of which depends on the kind and amount of the polymeric layer applied on the cores as well as type of superdisintegrant in core tablet. The developed system offers a simple and novel technique for pulse release of drugs. From the results it is concluded that the PRT we prepared could achieve a rapid release after lag time of 4±0.2h with the relatively low variability. The drug release profile of optimized batch K6+F4 was found to be follow korsmeyer and peppas model. So it is concluded that formulation release the drug by diffusion and erosion method