Development And Preparation Of Yiganqing Sustained-Release Hydrophilic Gel Matrix Tablet

Yiganqing,a prescription of traditional Chinese medicine,composed of two Chinese herb medicine—Penthorum chinense Pursh and Hypericum perforatum L., is clinically curative for hepatitis B.This thesis aimed at developing an oral sustained release dosage form of Yiganqing to prolong its action time and improve the patients' compliance and the rationality of drug administration.This study successfully developed and prepared a sustained release tablet dosage form of Yianqing,whose dissolution mechanism and quality standard were also demonstrated and established.Firstly,the HPLC determination methods of the active components—hypericin and quercetin in this preparation were developed;and also,the dissolution condition and the UV determination method of the dissolution profiles were developed.Secondly,the selection experiments of adjuvant,adhesive material,and lubricators were executed.The optimum matrix formulation of Yiganqing sustained release tablet was found to be a combined system of HPMC K4M and PVP K30 with their amounts at a certain ratio,through a series of screening and optimizing experiments,including the selection of matrix materials and their amounts.The optimum amounts of HPMC K4M and PVP K30 in the matrix system were found out through central composite design-response surface methodology.Furthermore,the preparation processes including the mechanical strength of the tablets were optimized.The final preparation formula and preparation technology were:Penthorum chinense Pursh extract 64.8 g,Hypericum perforatum L.extract 64.8 g,HPMC K4M 42.9 g,PVP K30 44.48 g,lactose 103.78 g, magnesium stearate 3.24 g,the extracts and adjuvants were sieved by a 80-mesh sieve,a certain amount of 3%PVP K30 absolute alcohol were added to prepared granules by means of fast agitating and shearing.The resultant granules were sieved through a 30-mesh sieve,and dried at 60℃for 2 h,then passed through 30-mesh sieve.The press machine parameters were adjusted to keep the tablet weight at 0.32 g±5%,the pressure was set at a certain value to keep the tablet hardness at 3～5 kgf. Under the above condition,1000 tablets were prepared.The identification,determination and dissolution test results of three batches of Yiganqing sustained tablets demonstrated that the producing process is feasible and stable.The dissolution profile of this preparation was investigated.Its dissolution mechanism was found to be a way of combined effects of corrosion and diffusion with corrosion as the dominant one.The percentage of corrosion effect increased with the dissolution time.pH condition and ionic strength were found to affect significantly on the dissolution behavior,the dissolution rate was higher under higher pH value condition or under bigger ionic strength condition.At last,the quality standard,including the characteristics,identification,determination,and dissolution profile etc.,was developed for stable producing.The research results manifest that:this tablet formulation has a satisfactory characteristic of sustained release for 12 hours;this preparation technology has a good reproducibility and stability;the developed quality standard is reliable and can be used for the quality control of this preparation.