Stimuli-Responsive Supramolecular Interface

Stimuli-responsive supramolecular assembly modified interfaces withtunable surface properties and desirable interfacial functions, have attractedsubstantial research efforts. Supramolecular assembly formed on the basis ofhost-guest interaction of azobenzene and cyclodextrin (CD) has been wellestablished in solution. However, there are very rare works that reportinterfacial supramolecular assembly of CD and azobenzene and theirbehaviors.In this thesis, stimuli-responsive supramolecular interfaces with novelinterfacial functions are fabricated by transferring controlled supramolecularassembly of CD and azobenzene from solution to suface.(1)A light-driven molecular shuttle on surfaces based on reversibleinclusion and exclusion reactions between azobenzene and CD is fabricated,which can switch its surface wettability.(2) The fabrication of a light or pH dual-responsive reactivatedbiocompatible interface using the photocontrolled reversible host-guestinteraction between photo-responsive azobenzene-containing self-assembledmonolayer (Azo SAM) and the pH-responsive poly(acrylic acid) polymergrafted with CD moieties (PAA-g-CD) is reported, which is used forreversible immobilization of redox proteins triggered by dual external stimuli.(3)A pH-responsive reactivated biointerface is fabricated using aninclusion reaction between Azo SAM and pH-responsive poly(ethyleneglycol)-block-poly(acrylic acid) grafted with CD (PEG-PAA-g-CD). ThepH-responsive interface can be switched between an extended state and arelaxed state for the reversible resistance of cytochrome c adsorptioncompletely in cooperation with protein-resistant PEG.(4)Photoswitchable bioelectrocatalysis of glucose with glucose oxidasein an "On-Off" state is fabricated from host-guest chemistry at interface by using the photocontrolled reversible immobilization and detachment offerrocene-labeled redoxpolymer as mediators.By introducing controlled supramolecular assembly of azobenzene and CD fromsolution to suface, several novel stimuli-responsive supramolecular interfaces arefabricated and studied. It is anticipated that this line of research can be furtherextended to fabricate functional biosurfaces for photoswitchable biofuel cells andoptoelectronic systems, controlled biosensors and energy conversion, informationstorage and processing.