Construction And Photoregulation Of Supramolecular Nano-Assemblies Based On Aromatic Guests And Macrocyclic Compounds

Developing novel supramolecular assembly with special morphology or functions is still an important research direction in the field of supramolecular chemistry.For supramolecular chemists,achieving function optimization and morphology regulation with a simple and convenient manner is a significant advantage than synthetic chemistry.In this paper,firstly,we use the strong bonding ability of cucurbituril towards guest molecules to build two kinds of stable supramolecular assembly with special functions and investigated their functions and applications;secondly,through specific host-guest interactions of several water-soluble macrocyclic hosts such as cyclodextrins,water-soluble crown ethers,cucurbituril,pillarene with azobenzene and viologen species we successfully regulated the assembly behavior of diphenylalanine.Specific contents are as follows:(1)A water-soluble supramolecular polypseudorotaxane was prepared via the host-guest interaction of cucurbit[8]uril and the Ru(bpy)3 complex with bis-naphthalene groups.By employing the intrinsic properties of Ru(bpy)3 complex,the linear polypseudorotaxane was used to induce DNA condensation,as inhibitor for DNA cleavage enzymes and trace the translocation of DNA into 293 T cells efficiently.(2)A fluorescent blocky supramolecular assembly was prepared via the host-guest interaction of cucurbit[8]uril and the Ru(bpy)3 complex which has six-naphthalene groups.At solid state,the supramolecular assembly was successfully used as molecular sponge to absorb negatively-charged molecules efficiently.(3)A nano-scaled photo/chemo dually interconvertible system was constructed through the supramolecular assembly of photo-responsive azobenzene-diphenylalaine(Azo-FF)with ?-cyclodextrin.(4)We have succeeded to modulate the aggregate morphology of a single MV–FF from straight fiber to rod,dodecahedron,nanohelices and cube,without introducing any chemical modification but through supramolecular complexation with different hosts,i.e.CB[7],CB[8],pillar[5]arene,and tetrasulfonated 1,5-dinaphtho-32-crown-8(DNC).