| The purpose of present study to develop Gastro-retentive drug delivery formulation for enhancing GRT including the
physiological and formulation variables affecting gastric retention. It is a widely employed approach to retain the dosage form
in the stomach for an extended period of time and release the drug slowly that can address many challenges like poor
bioavailability. Floating microspheres were prepared by Solvent evaporation (oil-in–water emulsion) technique. In this 225mg
polymethyl methacrylate (PMMA) were dissolved in a mixture of dimethyl formamide and dichloromethane (1:1) at room
temperature. And 75mg Nizatidine hydrochloride was added in the above mixture. This was poured into 250ml water
containing 0.02% tween 80, maintained at a temperature 30-40oC and subsequent stirred at ranging agitation speed for 20
minute to allow the volatile solvent to evaporate.The microspheres formed were filtered, washed with water and dried in
vaccum. The prepared Floating microspheres were characterized in different way like size distribution 131.4±1.6µm and
89.5±1.4% entrapment efficiency was found, In vitro floating test of optimized floating microspheres formulation was
studied in SGF (pH 1.2). The percent Cumulative amount of drug release was found 87.2±2.6% in SGF (pH 1.2), 90.2±3.5%
in SIF (pH 6.8) and 93.2±3.5 % in PBS (pH 7.4) upto 24 hrs. The ulcer protection of the microspheres formulation were
79.84% as compared to the nizatidine pure drug (66.05%) in ulcer induced rats. The C-max value Of Nizatidine as obtained
from the graph was 575.14 ± 55.43 ng/ml with T-max value 2h and for formulation was 206.58 ± 7.71 ng/ml. Floating
microspheres drug delivery system provides the possibility of enhancing the bioavailability and control the release of
formulation exhibiting absorption window by prolonging the gastric emptying time of the dosage form ensuring availability of
drug at the absorption site for the desired period of timeddd |
