title: Multi-responsive magnetic microsphere of poly(N-isopropylacrylamide)/carboxymethylchitosan hydrogel for drug controlled release.
abstract: Multi-responsive composite microspheres were synthesized via an in situ free radical polymerization of thermo-responsive poly(N-isopropylacrylamide) (poly(NIPAAm)) in the presence of carboxymethylchitosan (CMC) and magnetite nanoparticles (MNPs) followed by glutaraldehyde crosslinking. Formulation conditions of the composite microspheres were tuned such that spherical microspheres with narrow size distributions were obtained (30.0±1.0μm in diameter). They responded well to an applied magnetic field and showed water swelling responses to the change in solution pH and temperature. The release of an entrapped indomethacin model drug was accelerated when the solution temperature was above its lower critical solution temperature (LCST) (50°C) or when the solution pH was in basic conditions (pH 11). These responsive properties can be used as triggering mechanisms for releases of the entrapped drugs from the microspheres, indicating their great potentials for use in controlled release applications.
authors.affiliation: Department of Chemistry and Center of Excellence in Biomaterials, Faculty of Science, Naresuan University, Phitsanulok 65000 Thailand.
authors.forename: Nantharak
authors.initials: N
authors.lastname: Rodkate
authors.affiliation: Department of Chemistry and Center of Excellence in Biomaterials, Faculty of Science, Naresuan University, Phitsanulok 65000 Thailand. Electronic address: methar@nu.ac.th.
authors.forename: Metha
authors.initials: M
authors.lastname: Rutnakornpituk
mesh_terms: D000180:Acrylic Resins; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D048271:Chitosan / Q000031:analogs & derivatives*; D003692:Delayed-Action Preparations; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007213:Indomethacin / Q000008:administration & dosage; D008280:Magnetics; D008863:Microspheres; D013696:Temperature
chemical_list: D000180:Acrylic Resins; D003692:Delayed-Action Preparations; C514968:carboxymethyl-chitosan; C052970:poly-N-isopropylacrylamide; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D048271:Chitosan; D007213:Indomethacin
keywords: Carboxymethylchitosan; Magnetic; Microsphere; Multi-responsive; Nanoparticle; Poly(NIPAAm)