聚合物单分子胶束构筑与原位制备金纳米粒子的调控机制

Polymeric micelles assembled by amphiphilic block copolymer spontaneously with well-defined core and surrounding shell as well as attractive multi-functional properties can be used as prospective nanocarriers in a wide range of applications. However, the dynamic nature of self-assembled micelles renders them undesired dissociation or aggregation, under varying experimental conditions, influencing their application performance. In the proposal, stable unimolecular micelles will be built. The effects of polymer molecular structures and environmental factors on unimolecular micelles formation and structures will be explored to elucidate formation mechanism and structures regulation by combination of computer simulation, theoretical analysis and experiment. Amine groups of unimolecular micelles will be utilized to in situ prepare gold nanoparticles. Systematic methods will be exploited to investigate preparation, dispersion and stabilization mechanism of gold nanoparticles. The research results would be expected to guide the design and control of polymeric unimolecular micelles, and to establish the theoretical and technological foundation for cancer theranostic application.

聚合物胶束具有疏水内核、亲水外壳及易多功能化修饰等特点，在催化、医药、纳米材料等领域具有广阔的应用前景，但是，通过分子自组装形成的胶束易受环境因素的影响出现结构解体或聚集，从而影响其应用性能。本项目将构筑结构稳定的聚合物单分子胶束，综合运用计算机模拟、理论计算和实验表征等技术，研究聚合物分子结构、环境因素对单分子胶束形成的影响规律，阐明调控聚合物单分子胶束结构的机制；并利用聚合物单分子胶束中的胺基原位还原制备金纳米粒子，探究胶束和聚合物结构对金纳米粒子制备、分散和聚集行为的影响机制。研究成果将有望指导聚合物单分子胶束的设计与调控，也为癌症诊疗一体化体系的研究和开发提供理论和技术支持。

聚合物单分子胶束仅由一个聚合物分子构成，是一类结构稳定的药物载体，在体内循环过程中不易受流体剪切、稀释和盐离子等影响。本项目设计合成出β-环糊精星形聚合物，利用原位还原和疏水作用，构筑出同时载金纳颗粒（AuNP）和抗癌药物的多功能单分子胶束。综合运用分子动力学和介观模拟技术、胶体化学理论计算和实验测试等手段，在微介观尺度上探究了单分子胶束的形成机理、聚合物结构和环境因素对单分子胶束形成和结构的影响规律，以及影响AuNP原位还原、形貌和稳定性的关键因素。.针对当前单分子胶束药物载体的关键问题：长亲水链导致的药物装载和释放性能较差，采用介观模拟方法探究了短亲水链单分子胶束稳定性的交联和静电协同增强机制，实现单分子胶束同时具有稳定性和良好药物控释性能。通过在聚合物结构中引入刚性嵌段，也能够提高聚合物药物载体的载药和药物控释性能。本研究有望对单分子胶束药物载体的结构和多功能设计和合成提供指导和理论依据。