Preparation Of Baicalin-loaded Liquid Suppository And The Evaluation Of In Vitro-in Vivo Characteristics

In this paper, a thermosensitive in situ gel (liquid suppository) including Baicalin (BC) for rectal administration was prepared with Poloxamer 407 (P407), a thermosensitive high molecular material. First of all, the physical properties of BC were studied. The solubility of BC in various medium were determined by UV method, and the experiments of drug solubilization were also carried on. And then the formulation screening was performed by taking sol-gel transition temperature and many other factors. The best formulation of BC thermosensitive gel was Poloxamer? F127- SA-PEG4000 (18:0.5:1.0), which had a Tgel of 35℃. Furthermore,the RP-HPLC method was developed to determine and calculate the pharmacokinetic parameters in vivo and in vitro of BC, the rules of drug release were indicated. The rules of drug release in vitro were studied by the dialysis bag-pulp method.There were some distinct advantages of the thermosensitive in situ gel in the drug release of speed and extent. It was indicated that the quick-release of BC was promoted by this type of formulation, and by the model fitting, the mechanism of drug release followed the non-Fickian.Pharmacokinetics study in vivoindicates compared with the control group, the study group had a shorter tmax, but a higher Cmax, the absorption rate of the study group was much faster then that of the control group at every specified time.In short, by the studies of BC and the thermosensitive in situ gel, the drug loaded thermosensitive in situ gel was prepared, which was more safe, more effective and more stable. In order to develop the new dosage forms of poorly water-soluble drug and chinese medicine.