Silymarin Solid Dispersion And Its Gel Matrix Tablets,

Silymarin(Silibinin), a chemically defined plant-based drug, is used as a hepatoprotective agent. It acts as a radical scavenger, removing the reactive radicals resulting from liver detoxification of xenobiotics. It is also a very effective antidote in the treatment of severe intoxications by toxic chemicals such as poisonous mushrooms. This drug is used also in the treatment of some inflammatory diseases of the kidney, stomach and skin, and as a chemopreventive agent in human carcinogenesis. The thesis was aiming at preparing of solid dispersion with povidone(PVP) to improve bioavailability of silymarin and preparing of sustained-release tablet(SRT) to improve the patient compliance, maintain relatively constant plasma concentration, by using hydroxypropylmethylcellulose (HPMC) as basic matrix material.According to the literature, UV spectrophotometry was developed for in vitro assay of physicochemical properties, content and drug release. High-performance liquid chromatography (HPLC) was applied in the determination of plasma concentration in Beagle dogs.In addition, the absorption kinetics was obtained by using the in situ perfusion method in rats. It was showed that the upper and middle part of the small intestine was the preferred absorption segment. The absorption of Silymarin fit the passive diffusion mechanism and first order kinetics.The influence of different kinds of carriers and agent-carrier proportion on the dissolution of Silymarin was examined. Finally, it showed that PVP K15 was the best carrier. X-Ray powder diffraction analysis exhibits that the solid dispersion of Silymarin- PVP K15 was in an amorphous form, and the...