PREFORMULATION, FORMULATION DEVELOPMENT AND DRUG RELEASE STUDIES OF DIPYRIDAMOLE FLOATING MICROBALLOONS

For the drugs possessing stomach and upper intestine as the absorption window, it has become high practical importance to improve their gastric residence time. The in vitro performance of the drug delivery being highly variable is ascertaining as gastric emptying is one of the complex mechanisms. Intense researches are being carried out for the development of multiparticulate systems, which are of greater importance than the single unit dosage forms in oral drug delivery. Floating microballoons offer more reproducible drug absorption, reduce the risk of local irritation, and improve the bioavailability of the drug. In the current research work, Dipyridamole, a BCS class – II drug was formulated as controlled release microballoons using ethyl cellulose as polymer and span 80 as the surfactant to improve the gastric retention of the drug. Preformulation studies viz. solubility, partition coefficient, micromeritics, and the drug excipient compatibility studies using Fourier transform infrared spectrophotometer and Differential Scanning Calorimeter were carried out. The emulsion solvent evaporation method was employed to develop controlled release dipyridamole floating microballoons. Different formulations of floating microballoons were formulated by considering five process and formulation factors viz. surfactant concentration, volume of solvent, volume of internal phase, polymer concentration, and rotational speed. All the formulations were subjected to in-vitro drug release studies, and the lowest and highest release rate was found to be 0.096 hr^-1 and 0.251 hr^-1 in the formulations F34 and F15, respectively. The Peppas n values of all the formulations were above 0.5, indicating the drug release mechanism was non-fickian diffusion.