In this work, a UV-Visible light controlled supramolecular system based on ethyl cellulose （EC） was constructed, combining the host-guest interaction of β-cyclodextrin （β-CD） group and trans-isomer of azobenzene...In this work, a UV-Visible light controlled supramolecular system based on ethyl cellulose （EC） was constructed, combining the host-guest interaction of β-cyclodextrin （β-CD） group and trans-isomer of azobenzene （tAzo） group. To link β-CD to the hydrophobic section, renewable EC was used as macroinitiator to initiate the polymerization of ε-caprolactone （ε-CL） to form biocompatible and biodegradable comb copolymer EC-g-PCL, and β-CD was attached to the end of PCL side chain via click reaction. Meanwhile, hydrophilic PEG-tAzo was obtained by N,N＇-dicyclohexylcarbodiimide （DCC） coupling. Then, the structures of the products were characterized by nuclear magnetic resonance （NMR） and gel permeation chromatography （GPC）. Subsequently, with the formation of inclusion complexes by β-CD and tAzo groups, the obtained EC-g-PCL-β-CD/PEG-tAzo supramolecular system self-assembled in water with hydrophobic EC-g-PCL-β-CD as core and hydrophilic PEG-tAzo as shell. Furthermore, dynamic light scattering （DLS） and transmission electron microscopy （TEM） were utilized to investigate the particle size and size distribution, while NMR and UV-Vis spectra were applied to explore the UV-Visible light stimuli-responsiveness of the micelles.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.21174076 and 21374053)the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20120002110015)
文摘In this work, a UV-Visible light controlled supramolecular system based on ethyl cellulose （EC） was constructed, combining the host-guest interaction of β-cyclodextrin （β-CD） group and trans-isomer of azobenzene （tAzo） group. To link β-CD to the hydrophobic section, renewable EC was used as macroinitiator to initiate the polymerization of ε-caprolactone （ε-CL） to form biocompatible and biodegradable comb copolymer EC-g-PCL, and β-CD was attached to the end of PCL side chain via click reaction. Meanwhile, hydrophilic PEG-tAzo was obtained by N,N＇-dicyclohexylcarbodiimide （DCC） coupling. Then, the structures of the products were characterized by nuclear magnetic resonance （NMR） and gel permeation chromatography （GPC）. Subsequently, with the formation of inclusion complexes by β-CD and tAzo groups, the obtained EC-g-PCL-β-CD/PEG-tAzo supramolecular system self-assembled in water with hydrophobic EC-g-PCL-β-CD as core and hydrophilic PEG-tAzo as shell. Furthermore, dynamic light scattering （DLS） and transmission electron microscopy （TEM） were utilized to investigate the particle size and size distribution, while NMR and UV-Vis spectra were applied to explore the UV-Visible light stimuli-responsiveness of the micelles.
