PREPARATION, CHARACTERIZATION AND RELEASE PROFILES OF SPRAY DRIED CONTROLLED RELEASE MICROPARTICLES OF FAMOTIDINE, RISPERIDONE, ZIPRASIDONE AND TRAMADOL HCl

The aim of the present study was to prepare and evaluate controlled release microparticles of four drugs using blend of HPMC K4M by spray drying technique. The drugs used were famotidine (histamine H2-receptor antagonist), risperidone, ziprasidone (antipsychotic) and tramadol HCl (centrally acting analgesic). The angle of repose, Carr’s index and tapped density were well within the limit, indicating good flow potential for the microparticles. Fourier transform infrared spectroscopy (FTIR) spectra showed that the encapsulated drug was stable in the prepared formulations. The prepared formulations were analyzed quantitatively for the amount of encapsulated drug. From the encapsulation efficiency and in vitro drug release data A1, A4, A7, A10 was selected as optimized formulation. The optimized formulation A1, A4, A7, A10 shows the drug release of 72.49%, 71.38%, 72.95% and 74.67% up to 8 hrs, respectively. The yield was found to be in range of 45.1 ± 0.24% to 55.3 ± 0.29% and encapsulation efficiency in the range of 58.23 ± 0.36% to 78.41 ± 0.17% for all the batches. The release kinetics for all the formulations indicated that drug release followed peppas model. The optimized formulations were stable over a period of 3 months.