As a dual-stimuli-responsive polymer, α−cyclodextrin-bearing telechelic poly(2-isopropyl-2-oxazoline)(CD-PiPrOx-CD) was prepared by living cationic ring opening polymerization followed by click reaction (copper-catalyzed alkyne-azide cycloaddition). The phase transition temperature (TCP) of CD-PiPrOx-CD (0.33 mM) in 10 mM PBS solution (150 mM NaCl, pH 7.4) was 42.9 °C, and dramatically changed to 8.5 °C upon addition of the azobenzene-bearing penta(ethylene glycol)(Az-5EG)(3.3 mM). A change in the TCP was again observed for the mixture solution of CD-PiPrOx-CD and Az-5EG upon ultra-violet (UV) irradiation at 365 nm. Under 365-nm UV irradiation for 30 min, the TCP of CD-PiPrOx-CD changed to 41.3 °C, indicating the release of Az-5EG from the host-guest complex. During alternate irradiation at 365 and 254 nm, the TCP changed in a fully reversible manner.
Bibliographical noteFunding Information:
This work was supported by the Mid-Career Researcher Program [ 2017R1A2A1A17069537 ] funded by the National Research Foundation (NRF) of Korea .
© 2019 Elsevier Ltd
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Materials Chemistry