The Design And Evaluation Of Thymosin Hydrophilic Matrix Sustained Release Tablets

Thymopolypeptides, obtained from mammal thymuses, more specifically from calf or pig thymuses, was shown to be useful in the treatment of secondary immunodeficiencies, such as physiological immunosenescence and immunodepression induced by antitumour treatments or infectious diseases. To reduce the side effects and maintain relatively constant plasma concentration, a sustained release tablet of twice daily administration was designed and prepared by using hydroxypropyl-methycellulose (HPMC) as basic matrix material.According to literature, the method of Lowry was developed for in vitro assay during the studies of content and release. Carbon granular clearance test was applied in the determination of OD in rabbits.In the development of HPMC matrix tablet, the effective factors on the drug release were studied by the method of Lowry. The result was found that the release of Thymopolypeptides decreased with the increasing of the quantity of HPMC, the wetting agent and the compression pressure can make thymopolypeptides release rate change. The formulation was obtained by orthogonal design test, the sustained release tablets were coated with Opadry enteric white to avoid to be destroy in the gasteic juice. Drug reseasing rate followed the Higuchi equation. The tablets released mainly by diffusion from HPMC matrix. Stability studies of preparation demonstrated that light, temperature and moisture had little effect on thymopolypeptides sustained...