Pharmacophore an International Research Journal
The purpose of this research was to formulate floating tablets of Nicardipine hydrochloride so as to prolong its gastric residence time and increase its bioavailability as it has good solubility at low pH values. Melt granulation technique was used for preparing the floating tablets using polyethylene glycol 6000 as bioadhesive hydrophilic meltable polymer and different viscosity grades of direct compressible polymer like hydroxyl propyl methylcellulose, and gas generating agent like sodium bicarbonate and ethyl cellulose as floating enhancer material. Pre-compressional and post compressional parameters were evaluated. The mechanisms of drug release were analyzed using different kinetic models. The concentrations of PEG 6000, HPMC K4M, were selected as independent variables and drug release values at t50% and t80% as dependent variables. Formulation P6 was selected as an optimum formulation as it showed more similarity in dissolution profile with theoretical profile (similarity factor, f2 = 0.98). It was also observed that increase in viscosity of the HPMC grade resulted in increased floating lag time with simultaneous increase in floating duration. The in vivo studies in albino rabbit showed good floating duration for the optimized formulation. The FTIR/DSC studies revealed no interaction between the drugs and excipients. It can be concluded from this study that the combined matrix system containing combination of high molecular weight hydrophilic polymers with increased viscosity minimized the burst release of drug from the tablet and achieved a controlled drug release which is otherwise difficult to achieve with only single polymer matrix.
