【作者】 晋兴华；

【导师】 张韻慧；

【作者基本信息】 天津大学 ， 应用化学， 2009， 博士

【摘要】 纳米结构脂质载体(nanostructured lipid carriers,NLC)是不同结构的固体脂质和液体脂质混合作为载体的新一代脂质纳米给药系统。NLC具有的特殊结构可以提高其载药能力和制剂的稳定性,能有效的控制药物的释放。NLC是结构复杂的多相体系,其配方组成以及制备工艺过程决定了NLC的微观结构进而影响着它的最终性能。本研究综合应用分子模拟、理论分析以及实验表征的手段,从分子动力学和介观动力学角度阐述了脂质纳米粒成形的机理,考察了NLC配方组成和制备工艺条件对体系微观结构的影响,把握了复杂结构的NLC给药体系的结构与性能的变化规律,建立起宏观条件-微观结构-药剂学性能的定量关系,从而达到对NLC给药系统的优化设计的目的。在NLC给药系统中,药物与载体以及脂质载体之间的相容性是决定NLC的微观和介观结构,载药能力,稳定性等药剂学性质的关键因素。本研究采用Flory-Huggins理论结合分子动力学模拟的方法,模拟计算药物与载体的溶解度参数,预测药物与不同载体以及不同载体之间的共混性能,从而筛选出理想的脂质载体及其配比用量。应用耗散粒子动力学(dissipative particle dynamics,DPD)介观模拟方法探讨了脂质纳米给药系统的配方组成和制备工艺对其介观结构与性能的影响。DPD模拟可以直观地反映实验测定难以展现的过程和现象,而且有效地阐述脂质纳米给药系统的介观结构和成形机理,定量地预测实验结果,对处方组成和工艺参数进行筛选和优化,为实验研究奠定了理论基础。在分子模拟筛选实验的基础上,采用D-最优混料试验设计方法进行多指标的同步优化脂质纳米给药体系,试验点数较少、结果可靠、预测精度高。对最优化的NLC进行药剂学评价,实验结果较好地吻合了分子模拟的理论预测,进一步证明了分子模拟预测的准确性和可靠性。本研究应用分子模拟技术进行脂质纳米给药体系的理论研究和设计优化,减少了反复的探索实验,缩短研究周期,节省大量的研究费用,加快药物制剂研究和开发的进程。分子模拟技术应用在药剂学领域中具有很强的实用价值,有助于促进药物制剂新技术的发展,为药剂学理论的研究开辟了新的研究方法。更多还原

【Abstract】 Nanostructured lipid carriers (NLC) composed of a solid lipid matrix with a certain content of liquid lipid are a new generation of lipid nanoparticle delivery system. The special structure of NLC improves its drug-loading capacity and stability, and effectively controls the release of drugs. NLC are complex multi-phase systems, whose composition and preparation parameters impose effect on their properties by means of changing their nanostructure. In this study, molecular simulation, theoretical analysis and experimental characterization are integratively used to expound the forming mechanism of lipid nanoparticles from molecular dynamics and mesoscopic dynamics, the effects on their nanostructures imposed by their composition and preparation parameters are studied, the changes of NLC structure and properties are grasped, the quantitative relationship of macroeconomic conditions, nanostructures and pharmaceutical performance are established.In NLC drug delivery systems, the compatibility of drug and lipid carriers is the key element to determine the structure of microscopic and mesoscopic, drug-loading capacity and stability. In this study, molecular dynamics simulation method combining Flory-Huggins theory is used to calculate solubility parameter of drug and carriers, predict the blends performance of drug and different carriers, and then screen out the ideal ratio of the amount of lipid carriers.The nanostructures and properties of NLC are further investigated with Dissipative Particle Dynamics (DPD) simulation technique. DPD simulation technique can show the processes and phenomena which are difficult to be displayed by experiments, and can effectively analyze mesoscopic structure and forming mechanism of lipid nanoparticle drug delivery system. Their composition and preparation parameters are screened and optimized by mesoscopic simulation and theoretical analysis. DPD simulation technique cannot only ensure qualitatively analysis of the experimental phenomena, but also quantitatively forecast of experimental results.In the basis of the molecular modeling experiments, D-optimal mixture experimental design is used to optimize synchronously NLC drug delivery system by multiple indicator, which has fewer test points, reliable results, and high-precision forecast. Based on the evaluation of optimal NLC, the experimental results better match the theoretical prediction of molecular simulation, which further proves the accuracy and reliability of molecular simulation forecasts.In this study, molecular simulation technology is used for theoretical research and designing optimization of lipid nanoparticle system, which can reduce repeated experiments, shorten the research cycle, save a lot of research costs, speed up the pharmaceutical process of research and development. Molecular simulation techniques used in the pharmaceutical field have a strong practical value, which contribute to the development of new pharmaceutical techniques and theories.更多还原