Development of Mucoadhesive Microsphere of Quinapril Hydrochloride for Treatment of Hypertension

Mucoadhesive drug delivery systems are very widely functional approach for delivery of system within the lumen of GIT to enhance drug absorption through the part of stomach with specific manner. Quinapril hydrochloride is the hydrochloride salt of quinapril, the ethyl ester of a non-sulfhydryl, angiotensin-converting enzyme (ACE) inhibitor, quinaprilat. The quinapril hydrochloride microspheres was prepared with a coat consisting of alginate polymer i.e. sodium alginate in combination of mucoadhesive polymer chitosan/ guargum by an ionic gelation process. The microspheres were evaluated for morphological character, particle size, micromeritic properties, percentage entrapment efficiency, in-vitro wash-off test and in-vitro release studies. The drug quinapril hydrochloride was study for the release over 24 h duration.  The retarding nature of system maximizing the medication discharge rate at the appropriate site within specified time period for enhancing the bioavailability of drug at desired site of action to give successful treatment to the patients experiencing hypertension The drug release of the microspheres (QLMM1 – QLMM10) was slow, extended and dependent on the composition of galactomannan concentration of polymer and stirring speed during formulation used. The mucoadhesive microspheres were adhered at intestinal pH due to highly swelling nature of composition of polymers at this pH. So, increase the adhesive strength and retarded the drug release of best composition of CH:GG in the ratio of 1:3 (QLMM6). Guargum is a highly viscous material having a property of more swelling nature due to presence of galactommannan constituent. Thus, drug release from QLMM6 was slow and extended over a period of 24 h and these microcapsules were found suitable for oral controlled release formulations. Keywords: Gastro-retentive drug delivery, Mucoadhesive microsphere, Quinapril hydrochloride, Pulsatile drug delivery system, Treatment of hypertension, Natural polymer