Hydralazine is a direct-acting vasodilator and has a short biological half-life (2-4 hours) due to significant first-pass metabolism with poor oral bioavailability.The aim of the current research is to reduce the frequency of dosing and enhance bioavailability to improve patient compliance by developing and systematically evaluating the sustained release of Floating alginate microbeads of Hydralazine hydrochloride.Using sodium alginate as the hydrophilic carrier in combination with different viscosity grades of HPMC such as HPMC K4M, HPMC K15M and HPMC K100M as drug release modifiers for the preparation of floating alginate microbeads of Hydralazine Hydrochloride by ionotropic gelation and cross-linking technique.Prepared beads were evaluated for percentage yield, particle size, micromeritic properties, drug entrapment efficiency, drug loading capacity, swelling ratio, in-vitro buoyancy studies, in-vitro release (in acidic buffer pH 1.2) and in-vitro release kinetic study.No significant drug-polymer interactions were observed from FT-IR studies.In fixed concentration of sodium alginate and calcium chloride and increases in the coating polymer concentration results increases in diameter of microbeads and also decrease the swelling ratio of beads.With the increase in coating polymer ratio, drug entrapment efficiency has been improved.All the formulations (F1 to F9) floated immediately or with a very short lag time and remained floating up to 12 hours.From the result of in-vitro dissolution studies reveals that the formulation F9 gave sustained release pattern of drug upto 12 hours (99.75%) and exhibited zero order kinetic followed by non-fickian diffusion transport of mechanism.Hence the formulated HPMC K100M coated sodium alginate beads can be used as an alternative and cheaper carrier for the oral controlled delivery of Hydralazine hydrochloride, especially for the treatment of congestive heart failure.
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