Preparation And Characterization Of Betulinic Acid Molecular Capsule

Betulinic acid is an important lead compound from the forest prodct. With the anti-viral, anti-tumour and low toxicity toward human, betulinic acid is suiatable for making chemical drugs. However, the very little content in plant tissue and hydrophibic property of betulinic acid can not satify the therapeutic demoneds but the preparation of pharmaceutical products. So, it is important to obtain a high-efficiency betulinic acid preparation method and demonstrate some hydrophilic betulinic acid new drugs.Firstly, betulinic acid was synthesized by a two-steps reaction based on the method of Kim, through the purifying of intermediate compound of betulonic acid. Fourier Transformed Infrared analysis and Mass analysis were used to characterize the final product. A quantitative analysis method of betulinic acid by Ultra-high Performance Liquid Chromatography was established. Through the purifying of intermediate compound of betulonic acid and optimizing betulonic acid dissolving solvent, the high purity of 98.2% betulinic acid product had been finally obtained.Secondly,6 of cyclodextrin derivitates are synthesized by the method of molecular design. For investigating the process of molecular recognition and selecting of the best suitable cyclodextrin derivitate, the interaction mechanism during the host-guest interaction is revealed. According to this mechanism, the optimized preparation parameters are obtained using the betulinic acid loading content as evaluation index. Furthermore, Fourier Transformed Infrared Spectrometer, Scanning Electron Microscope, Mass Spectrometer and Nuclear Magnetic Resonance Spectrometer are used to characterize the betulinic acid molecular capsules. Then, the investigation of the solubilizing effect for the betulinic acid is studied, and the final betulinic acid molecular capsule is obtained.Finally, to evaluate the cytotoxicity of betulinic acid molecular capsule, an in vitro test against human cancer cell line HeLa was performed. The anti-tumor effect against HeLa cell line is tested by MTT assay. The IC50 values of betulinic acid molecular capsules are tested and compared to the IC50 value of betulinic acid DMSO solution or betulinic acid water suspension. The results give a fundamental evaluation of the novel betulinic acid molecular capsule against tumor cells.