ABSTRACT
The present study involves preparation and evaluation of gastric-mucoadhesive microparticles with Metformin Hydrochloride as model drug for prolongation of gastric residence time. The microparticles were prepared by the emulsification solvent evaporation technique using polymers of Carbomer 934p [C] and Ethylcellulose [EC]. The microparticles were prepared by emulsion solvent evaporation method [O1/O2]. Disc formulations were prepared by direct compression technique from microparticles. In the current study, gastric-mucoadhesive microparticles with different polymers ratios [CP:EC] were prepared and were characterized by encapsulation efficiency, particle size, flowability, mucoadhesive property and drug release studies. The best polymers ratio was 1:3 [F2] with Carbomer 934p [as mucoadhesive polymer] and ethylcellulose [as retardant polymer], respectively. The production yield microparticles F2 showed 98.80%, mean particle size 933.25 mm and loading efficiency%98.44. The results were found that microparticle discs prepared had slower release than microparticles [p > o.o5]. The microparticles exhibited very good percentage of mucoadhesion and flowability properties. The release of drug was prolonged to 8 h [71.65-82.22%] when incorporated into mucoadhesive microparticles. The poor bioavailability of metformine is attributed to short retention of its dosage form at the absorption sites [in upper gastrointestinal tract]. The results of mucoadhesion study showed better retention of metformine microparticles [8 h] in duodenal and jejunum regions of intestine [F1, 1:2 ratio of CP:EC]. Therefore, it may be concluded that drug loaded gastric-mucoadhesive microparticles are a suitable delivery system for metformin hydrochloride, and may be used for effective management of NIDDM [Non Insulin Dependent Diabetes Mellitus]