Study On PH - Dependent Snow Retention Pellets

We change the tradition Xinxue pills to sustained-release pellets, In order to reduce the amount of medical eat, making patients to have it in time,TLC methods were used to identify Geniposide, Borneo, Artificial bezoar and Andrographolide in Xinxue pellets. the method of HPLC for testing their contents in preparation.The optimal extracting processes were determined by orthogonal experiment with the content of effective components:Geniposide and Andrographolide. We investigate the solvent amount, extracting time and extracting times, make sure the ultimate process:the herbs were extracted with 8-fold water for 2 hour by decoction, and repeated for 2 times. The result indicated that extracting process was stable, and the industry manufacture can refer to it.To investigate the absorption character of Geniposide in the intestine, the absorption kinesics and absorption position were studied by utilization of rat mould, to carry out the experiment that single pass perfusion at rat intestinal. the result indicated that the Geniposide has good absorption at all intestine. parameters were decrease at jejunum, ileum, duodenum, colon. Medical absorption don’t correlated with medical concentration and pH values. It was showed that the absorption of Geniposide was passive absorb mechanism.Preparation Xinxue pellets used the method of bed-coating, adhesive agent was water, The drug-loaded pellets were prepared with the cores of pellets that were maded of cane sugar and starch. Optimized processing conditions were obtained after the study of formulation factors and processing factors. The pellets produced were of good sphericity, proper hardness and good reproducibility. The average recovery of pellets to obtain by passing the mesh 16-30 was 70%.We prepared three pellets using the pH dependent adjuvant acrylic resins of different types. Pellets were covered with acrylic resinⅣthat coating film dissolves at in stomach and the medical will released. Acrylic resinⅡand acrylic resinⅢwas also used for coating to release drug at the duodenum, the third coating film we used the materials that can dispersed in the water. and medical can released in middle and lower part of small intestine. we make the xinxue sustained-released pellets by mixed three sorts of pellets of appropriate proportion. Investigated in vitro dissolution behaviors Of the Geniposide in the continuously simulated pH values,the optimal coating levels were thus determined at 8%, 15%and 15% respectively for the above three kinds of pellets.Pharmacokinetics study in vivo was studied in three healthy rabbits. Plasma concentration-time profiles after oral administration of sustained-release pellets and reference pellets were determined by HPLC. The non-compartment model results exhibit that theCmax、Tmax of sustained-release pellets are 64.25 ng·mL-1、1.67h,compared with reference pellets (Cmax、Tmax are 174.12 ng·mL-1、0.75 h), Cmax degrade significantly and Tmax extended. Its relative bioavailability was 85.84%. Good correlation existed between absorption percentage in vivo and release rate in vitro.