Study On Sustained Released Tablets Of Levalbuterol Hydrochoride

Objective:The new chiral drug levalbuterol hydrochloride was used for asthma therapy,which was select as the model drug and was prepared the sustained-release tablets including its effective time and bioavailiability. Comparing with the ordinary preparation, the sustained-release tablets diminish fluctuation of blood drug level and degrade the adverse reaction. So this kind of dosage form was a ideal sustained-release system.Method: The core tablets were prepared by wet granulation compression, combing with matrix-sustained release technique, the levalbuterol hydrochloride sustained-release tablets, which extend the drug release to 12 hours in vitro were prepared by using latex coating technique. The prescription of sustained-release tablet was selected by drug release investigation. Base on single-factor tests about prescription, the optimal prescription was selected by orthogonal design. The optimal formulation was authenticated by in vitro release determination. The drug release profile was analysis by using different equations. The drug release mechanism of sustained-release tablets was investigated by fitting drug release model. The quality standard of preparation was studied. Then the stability of sustained-release tablets was investigated.Result:The average cumulative release of optimization is 2h(27.99%), 4h(54.64%), 8h(82.91%), 12h(96.31%). The drug release profile in vitro was followed Weibull model equation. The mechanism of drug-release was diffusion and corrosion. The content and limited substance and drug release were qualified. Stability studies of preparation were shown that hight temperature and light have not obvious effect on L-SBA sustained-release tablet, but the humidity has some effect on the appearance and realese rate of L-SBA sustained-release tablet. The preparation should be stocked in cool and dry place. Conclusion : The sustained-release tablets were prepared by adjusting the prescription of core tablet and coat-layer. The drug release was complete after 12h.The HPLC method was suitable for the quality control of the preparation. The tablet should be packed in moistureproof material and preserved under cool and dry condition.