Dai Xingxing, Ding Haiou, Yin Qianqian, Wan Guang, Shi Xinyuan, Qiao Yanjiang
Beijing University of Chinese Medicine, Beijing 100102, China; Key Laboratory of TCM-information Engineer of State Administration of TCM, Beijing 100102, China.
Civil Aviation General Hospital, Beijing 100123, China.
J Mol Graph Model. 2015 Apr;57:20-6. doi: 10.1016/j.jmgm.2015.01.002. Epub 2015 Jan 15.
Platycodin, as a kind of plant based biosurfactants, are saponins which derived from the root of Platycodon grandiflorum A. DC. It has been confirmed that platycodin have the potential to enhance the solubility of hydrophobic drugs and function as the drug carrier, which depends on their micellization over critical micelle concentration (CMC) in aqueous solutions. With the purpose of investigating the effects of influencing factors on the micellization behavior of platycodin and obtaining the phase behavior details at a mesoscopic level, dissipative particle dynamics (DPD) simulations method has been adopted in this study. The simulations reveal that a rich variety of aggregates morphologies will appear with changes of structure or the concentration of saponins, including spherical, ellipse and oblate micelles and vesicles, multilamellar vesicles (MLVs), multicompartment vesicles (MCMs), tubular and necklace-like micelle. They can be formed spontaneously from a randomly generated initial state and the result has been represented in the phase diagrams. Furthermore, deeper explorations have been done on the concentration-dependent structure variation of spherical vesicles as well as the formation mechanism of MLVs. This work provides insight into the solubilization system formed by platycodin, and may serve as guidance for further development and application in pharmaceutical field of platycodin and other saponins.
桔梗皂苷作为一种植物源生物表面活性剂，是从桔梗（Platycodon grandiflorum A. DC.）根中提取的皂苷。已经证实，桔梗皂苷具有增强疏水性药物溶解度并作为药物载体的潜力，这取决于它们在水溶液中超过临界胶束浓度（CMC）时的胶束化作用。为了研究影响因素对桔梗皂苷胶束化行为的影响，并在介观水平上获得相行为细节，本研究采用了耗散粒子动力学（DPD）模拟方法。模拟结果表明，随着皂苷结构或浓度的变化，会出现多种聚集体形态，包括球形、椭圆形和扁球形胶束与囊泡、多层囊泡（MLV）、多隔室囊泡（MCM）、管状和项链状胶束。它们可以从随机生成的初始状态自发形成，结果已在相图中表示出来。此外，还对球形囊泡的浓度依赖性结构变化以及多层囊泡的形成机制进行了更深入的探索。这项工作为桔梗皂苷形成的增溶系统提供了见解，并可能为桔梗皂苷和其他皂苷在制药领域的进一步开发和应用提供指导。
