Based On The Preparation Of Cyclodextrin-terpyridine Vesicle System And The Study Of Stimulus Response Behavior

With the characteristic of simple and clear structure,vesicles have been studied as artificial membranes in the field of cytomimetic chemistry and biomimetic catalysis.Its morphological and structural changes are mostly related to the stimuli of the external environment,such as light,temperature,pH,the species of metal ions,host-guest interactions and so on.Based on the molecular recognition and supramolecular self-assembly principles,super-(amphiphilic)molecular aggregates that could response to stimuli of the external environment have been designed and synthesized.Typically,successful construction of supramolecular vesicles system has been discussed in this paper.Therefore,the function of this system is more intelligent with the flexibility of construction strategy.This would contribute to the development of the supramolecular chemistry theory and assembly.The paper is mainly divided into three parts:(1)Based on the molecular recognition and supramolecular self-assembly theory,a series of supramolecular building blocks were designed and synthesized by organic synthesis.They mainly consisted of terpyridine-?-cyclodextrin as host molecule,and azobenzene derivatives with different hydrophilic/hydrophobic long chains as guest molecules.The structures of all compounds were characterized by 1HNMR.(2)Using these building blocks,we successfully constructed supramolecular vesicles.It is found that the solvent ratio,the concentration of the host and the guest have a great influence on the self-assembly behavior of the super amphiphilic molecules.(3)In aqueous solution,we realized the assembly and disassembly of super(amphiphilic)molecular aggregates(vesicles)by changing the host-guest molecule and regulating the external environment.The spatial matching property of azobenzene group to the hydrophobic cavity of P-cyclodextrin((3-CD)provides the basic idea to construct super amphiphilic molecules through the interaction between the host and the guest.Futhremore,azobenzene can undergo photoisomerization under light irradiation,thus giving this super amphiphilic molecule system photoreversible property.In addition,because the terpyridine groups can complex to metal ions with different stability constant,adding metal ions will further induce the change of the morphology of supramolecular aggregates.Based on the above findings,we successfully constructed a supramolecular vesicle system;and by exposing to different environmental stimuli,such as UV-visible cyclic irradiation,different metal ions complexation,temperature&pH modulation,etc.,the assembly and disassembly of super amphiphilic molecular aggregates have been achieved.