Studies on the nanocomposites based on carboxymethyl starch-g-lactic acid-co-glycolic acid copolymer and magnetite

The study presents synthesis of the core-shell nanocomposite with magnetic properties based on carboxymethyl starch-g-lactic acid-co-glycolic acid (CMS-g-PLGA) and magnetite (Fe3O4). The polymeric matrix used for obtaining the nanocomposite particles was synthesized by the grafting reaction of carboxymethyl starch (CMS) with l-lactic acid (L-LA) and glycolic acid (GA) (1/20/7.5) in the presence of Sn(Oct)(2), as catalyst. CMS-g-PLGA/Fe3O4 nanocomposites were obtained by the double emulsion method (w/o/w). The nanocomposites were characterized by FT-IR, DLS technique, SEM, VSM and simultaneous thermal analyses (TG-FT-IR-MS). The main gases released by thermal decomposition of CMS-g-PLGA copolymer were analyzed with TGDTA/FT-IR/MS system on the temperature interval 30-650 A degrees C. The particles size of Fe3O4 was 273 nm and the saturation magnetization 63.20 emu g(-1), while for CMS-g-PLGA/Fe3O4 nanocomposite size was 773 nm and the saturation magnetization 41.96 emu g(-1). Zeta potential of the nanocomposite (-20.00 mV) and the functional groups from the surface confers a good stability in solutions and efficiency in complexation reactions with the active principles. The magnetite nanoparticles covered with a layer of biodegradable/biocompatible copolymer which embody structural units of CMS, LA and GA are well tolerated by the human/animal organisms and can be successfully used in biomedical or pharmaceutical fields.