利用多重响应性偶磷苯构建智能聚合物输送体系

It is an important strategy to construct smart materials via the discovery and application new host-guest system. Inspired by the remarkable light response performance of azobenzene, this project aims to utilize the higher reactivity P=P double bonds to substitute N=N double bonds then obtain the new guest molecule diphenyldiphosphene (DPP) with multiresponsive properties to the environmental stimulates. Based on this guest molecule, a new host-guest interaction system is developed and the constructed smart polymer drug delivery system with multiresponsive properties is promising to be applied in photodynamic therapy. Firstly, the multiresponsive properties to the stimulates such as light, acid and oxygen as well as the mechanism of the host-guest interaction with cyclodextrin will be explored thoroughly, also the feasibility to be used as the guest molecule will be discussed. Secondly, the DPP derivatives will be introduced into a polymer system using host-guest interaction. The effect of the multiresponsive properties on the assembly of the superamphiphile micelles will be investigated. Finally, the encapsulation and release of the photosensitizer via synergistic effect will be studied and its potential applications in photodynamic therapy will be evaluated. If this project works, it is undoubtedly to enrich the host-guest chemistry and promote the development of new smart materials.

发现和应用新型主客作用体系是构建智能聚合物材料的重要途径。本项目拟在已知偶氮苯具有良好光响应性能的基础上，利用活性更高的P=P双键替代N=N双键，实现新型客体分子偶磷苯对外界刺激的多重响应，以此发展一种新型主客相互作用体系，构建具有多重响应性的智能聚合物药物输送体系，以期在光动力治疗方面获得应用。首先，在预实验的基础上，系统研究偶磷苯的光、酸和氧等多重响应特性及其与环糊精的主客体作用机理，探讨其用作新型客体分子的可行性；其次，利用主客体作用将偶磷苯衍生物引入到高分子体系中，探索多重响应特性影响超两亲分子胶束组装行为的一般规律；最后，研究该胶束用于光敏剂的封装及在多重响应协同作用下的药物释放，探索其在光动力治疗中的应用。通过上述系统研究将有助于丰富主客体作用化学和促进新型智能材料的研制。

发现和应用新型主客作用体系是构建智能聚合物材料的重要途径。本项目拟在已知偶氮苯具有良好光响应性能的基础上，利用活性更高的P=P双键替代N=N双键，实现新型客体分子偶磷苯对外界刺激的多重响应，以此发展一种新型主客相互作用体系，构建具有多重响应性的智能聚合物药物输送体系，以期在光动力治疗方面获得应用。首先，系统研究了偶磷苯的合成，纯化，光、酸和氧等多重响应特性及其与环糊精的主客体作用机理，探讨其用作新型客体分子的可行性。实验结果表明，采用改进的Reesor方法可以制备偶磷苯，且产物对光、酸和氧等具有多重响应特性，与α-环糊精有一定的主客体作用。不过，该法制备的偶磷苯中尚存在较多五元环形式的偶磷苯低聚物，分离纯化非常困难，影响了其在主客体领域方面的应用。此外，该偶磷苯易于氧化，不利于构建智能药物输送体系。因此，采取了多种措施试图推进实验：1）以金属镁替代氢化锂铝提高偶磷苯产率；2)优化分离条件，以期获得较高纯度的单分子偶磷苯；3）筛选磷原子的对位取代官能团提高稳定性；4）氮磷偶联物的合成。值得指出的是，尽管这些努力并未保证该项目得以完全实施，但这只能证明偶磷苯类化合物用作客体分子的研究本身富有挑战性，其特殊性能仍是具有潜在的应用前景。