A novel starch-based stimuli-responsive nanosystem for theranostic applications

The aim of this study was to synthesis and characterization of a novel stimuli-responsive polymeric nanosystem for theranostic applications. For this purpose, starch was modified by itaconic anhydride to afford an itaconat-functionalized starch macromonomer (starch-IA). This macromonomer with carboxylic functional groups was subsequently adsorbed onto the surface of iron oxide nanoparticles (Fe3O4 NPs), and then copolymerized with N-isopropylacrylamide (NIPAAm) monomer via a 'free' radical initiated polymerization technique to produce a temperature-responsive magnetic nanohydrogel (MNHG). The chemical structures of all samples as representatives were characterized by means of Fourier transform infrared (FTIR) spectroscopy. The lower critical solution temperature (LCST), thermal responsibility, morphology, elemental composition, thermal stability, and magnetic properties of the synthesized MNHG were investigated. In addition, the methotrexate (MTX)-loading capacity (similar to 74%) and stimuli-responsive drug release ability of the synthesized MNHG were also evaluated. As results, we envision that the synthesized starch-g-PNIPAAm/Fe3O4 MNHG may be find theranostic applications, in part due to its smart physicochemical properties. (C) 2017 Elsevier B.V. All rights reserved.