Studies On The Preparation And Characteristics Of Baicalein Phytosome

Baicalein is a kind of main active constituents of Scutellariae Radix and widely used in clinical traditional Chinese medicine as a good prospective drug. Recent studies demonstrated various pharmacological effects of baicalein, such as anti-inflammator, antioxidative, antileukemic, cardioprotective, anti-HIV, antiproliferative, antitumor, etc. But its clinical applications is confined because of its sparingly solubility in water. In order to effectively improve its dissolution and absorption, baicalein phytosome is prepared. It may show some superior chemico-physical properties, enhance the absorption of the drugs, then combining baicalein phytosome with solid dispersion technology. The baicalein phytosome solid disperse system was prepared for better administration.The full work includes four contents, as follow:1. HPLC method determination was developed for the determination of baicalein in vitro, and it was validated by characterization of linearity, precision as well as accuracy. Meanwile, it was applied to in vitro assay of physicochemical properties, content and drug release. The methods were sensitive, accurate and simple, suiTab. for the analysis of the assay.2. on this section, the effect of such factors as the solvent of reaction, the ratio of reactants, the reactive temperature, the reactive time and the concentration of reactants was studied by the single factor tests and orthogonal design. The physic-chemical properties of baicalein phytosome including UV spectrum, crystal characteristics, IR spectrum and solubility were examined. The optimal conditions were obtained as follows:the ratio of baicalein to phospholipid was 1:4, the reactive time was 2h, the reactive temperature was 40℃and the concentration of reactants was 5 mg/ml. X-ray diffraction spectra indicated that drug encpasulated in the complex exhibited in an amorphous manner. UV and IR spectra didn't show new chemical bonds were formed in phospholipid complex. Moreover, there was a great improvement in the solubility of baicalein-phospholipid complex both in water and n-octanol.3. This study prepared the intestinal perfusate of baicalein and baicalein phytosome, Tween 80 was used as the solubilizer to prepare the perfusates, and Vit C was chosen as the antioxidant to improve the sTab.ilities of the drugs in the intestinal perfusate. Tween80 and Vit C in the perfusates were minimized through a series of comparisons to reduce their impacts on the drug's absorption. The uptake and wall intestinal permeability of baicalein and baicalein phytosome was tested with the use of intestine perfusion technique. The result recommend that baicalein in the combination with phospholipid is better than only used baicalein concerning bioavailability.4. The influence of different kinds of solvents, carriers and agent-carrier proportion on the dissolution of baicalein phytosome was examined. Finally, it showed that PVP K30 was the best carrier and absolute ethanol was solvent. The stability study of baicalein phytosome solid dispersion indicated it was unsTab. when it was exposed to illumination, high temperature and high humidity. Then its preparation must be stored in a dark, cool and dryness condition.