Synthesis, characterization, and drug release properties of macroporous dual stimuli responsive stereo regular nanocomposites gels of poly(N-isopropylacrylamide) and graphene oxide

Nanocomposite stereoregular hybrid gels of poly(N-isopropylacrylamide) were prepared in 1:1 methanol–water mixture in the presence rare earth yttrium trifluoromethanesulfonate Lewis acid and graphene oxide (GO). The nanocomposite gels were characterized by swelling ratio measurements at different temperatures and different pH, deswelling kinetics, scanning electrone microscopy, FTIR, thermogravimetric analysis, powder XRD, Raman spectroscopy, LCST measurement by DSC etc. Drug release experiments also done by using tramadol hydrochloride as a model drug to check their suitability in application. All results were explained on the basis of porosity, cononsolvency of the synthesis solvents, hydrophilicity, isotacticity, pH effect, interactions between solvents and polymer molecules, interactions between polymer and GO or interactions between GO and solvents etc. © 2016, Springer Science+Business Media New York.
KC2014ZDZJ0001A ZDSYS201507141105130 JCYJ20140509172719311 University of Akron 2013-7211-8496-02 National Natural Science Foundation of China: 21574086
We gratefully acknowledge the financial support from TUBITAK, Government of Turkey, through 2216 fellowship program for the foreign citizens and B??lent Ecevit University (#2013-7211-8496-02). The authors also thank the National Science Foundation of China (21574086), Nanshan District Key Lab for Biopolymers and Safety Evaluation (No. KC2014ZDZJ0001A), Shenzhen Sci and Tech research Grant (ZDSYS201507141105130), and Shenzhen City Science and Technology Plan Project (JCYJ20140509172719311) for financial support. We thank Prof. Kevin Cavicchi, University of Akron for comments on this manuscript.