DESIGN AND IN VITRO CHARACTERIZATION OF KETOPROFEN CORE IN CUP PULSATILE TABLETS FOR CHRONOMODULATED DRUG THERAPY.

The aim of the present investigation is to intend, develop and evaluate a pulsatile drug delivery containing a core-in-cup based system of dry coated tablet of ketoprofen based on chronomodulated approach for management of Rheumatoid Arthritis. This pulsatile system contained a core tablet surrounded by an impermeable outer shell and top cover layer. Core tablet contained the active ingredient acting as reservoir, ethylcellulose was used to form an impermeable outer shell, the top cover layer contained different hydrophilic polymers like SodiumAlginate, HPMCK4M, Sodium carboxymethylcellulose with different concentrations. The formulations were evaluated for various pre-compressional and post-compressional parameters. The effect of polymer properties and quantity of top cover layer, on the lag time and drug release was investigated. From the results it was evident that the lag time increased with increase in concentration of the plug layer, whereas drug release decreased. Plug layer polymers showed a lag time with rank order: SA<NaCMC<HPMC. The in vitro release studies revealed that the formulations containing HPMCK4M showed enhanced release when compared with other formulations. It was marked that there was no specific interaction between the drug and polymers from FTIR study. Optimized formulation was stable for three months under normal storage conditions. In conclusion a stable core-in-cup tablets of ketoprofen were successfully formulated which provided a desirable lag time followed by a required drug release and complied with chronotherapeutic objective of rheumatoid arthritis.