Triple stimuli-responsive amphiphilic glycopolymer

Triple stimuli (temperature/pH/photo)-responsive amphiphilic glycopolymer, poly(2-(dimethylamino)ethyl methacrylate- co -6- O -methacryloyl-1,2,3,4-di- O -isopropylidene-D-galactopyranose)- b -poly(4-(4-methoxyphenylazo)phenoxy methacrylate) [P(DMAEMA- co -MAIpGP)- b -PMAZO] was synthesized by atom transfer radical polymerization, followed by the hydrolysis of MAIpGP groups, resulting in the target product poly(2-(dimethylamino)ethyl methacrylate- co -6- O -methacryloyl-D-galactopyranose)- b -poly(4-(4-methoxyphenylazo)phenoxy methacrylate) [P(DMAEMA- co -MAGP)- b -PMAZO]. The composition, moleculer weight, and moleculer weight distribution of the resultant polymers were characterized by 1 H NMR and gel permeation chromatography. The micelles formed in aqueous solutions were simulated by various chemical and physical stimuli and characterized by dynamic light scattering, transmission electron microscopy, and UV-vis spectroscopy. It was found that the glycopolymer is responsive to three different types of stimulus (light, temperature, and pH). The poly(2-(dimethylamino) ethyl methacrylate) segments give thermo- and pH-responsiveness. The presence of the azobenzene moiety endows the block copolymer to exhibit light-responsiveness due to its reversible trans-cis isomerization conversion. The triple stimuli-responsive glycopolymer micelles can simulate biomacromolecues in vivo / in vitro environment and can be expected to open up new applications in various fields. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52 , 2131–2138