Study On Tetramethlprazine Phophate Controlled Porosity Osmotic Pump Tablets

The tetramethlprazine phosphate (TMPP) is a new calcium antagonist which has been widely used in clinic for cardiovascular and cerebrovascular diseases. On this study, two controlled porosity osmotic pump tablets (CPOP) were prepared, taking Solium Salicylic (SOSA) and Tetramthlprazine as the main drug respectively. Based on comprehensive pre-formulation research, polyvinylpyrrolidone (PVP), lactose, tartaric acid, sodium chloride etc were used as tablet core. Cellulose acetate(CA), Diethyl phthalate (DEP), Polyethylene Glycol-400(PEG-400) were selected as the coating material and acetone-isopropranol (4:1) co-solvent was employed as the coating medium.SOSA CPOP were prepared to study the basic formulation, preparation process and release rules of controlled porosity osmotic pump tablets. On this study, various factors which may effect drug release were investigated. The result indicated the acid substance, pore formers, plasticizer, coating thickness had great influence on drug release, while osmotic agents and polymer blokers had little influence on drug release. In order to optimize the formulation, uniform design was adopted. Regression equation and the best formulation were calculated by uniform design software. F test proved the regression equation was significant. Cumulative drug release of the best formulation at 12 h exceeded 90% and the linear correlation coefficient exceeded 0.99.The effect of various factors on drug release of TMPP CPOP was investigated. The result showed that osmotic agents, pore formers, plasticizer, coating thickness had great influence on drug release. In order to optimize the formulation, uniform design was adopted. Regression equation and the best formulation were calculated by uniform design software. F test proved the regression equation was significant. The verification of the best formulation proved drug cumulative release conformed to model of zero order, the cumulative release at 12 h exceeded 90% and the linear correction coefficient exceeded 0.99. It was proved the drug release was not influenced by the pH of dissolution medium, dissolution method and rotate speed. Free film diffusion experiment were employed to investigate the basic properties on tablet core and coating film of CPOP. The drug'solubility, solution'osmotic pressure and the rate of drug diffusion in different solution with different osmotic agent were determined. Using theoretical formula as a model, a new empirical formula had been deduced from experiments. It was proved calculation results from the formulae fit the test data satisfactorily.