Superparamagnetic Temperature-Responsive Ionic-Cross-Linked Polymeric Hybrid Nanocapsules via Self-Templating Approach

A facile strategy was developed for the preparation of the superparamagnetic temperature-responsive ionic-crosslinked polymeric hybrid nanocapsules via the self-templating approach based on the terpolymer (poly(tert-butyl acrylate-co-N-isopropylacrylamide-co-acrylic acid, (poly(t-BA-co-NIPAm-co-AA))) latex particles prepared by the emulsifier-free emulsion copolymerization as the self-templates. The multifunctional polymeric nanocapsules with a particle size of about 150 nm were obtained by etching the terpolymer self-templates with acetone after their surface carboxyl groups were ionic-cross-linked with the glycine-modified ferroferric oxide nanoparticles (Fe3O4-glycine). They exhibited the temperature-responsive charateristics with the lower critical solution temperature (LCST) of about 25 degrees C and the superparamagnetic properties, validated by the dynamic light scattering (DLS) and vibrating sample magnetometer (VSM) analysis. Their controlled release of a drug molecule (a model hydrophobic drug, dipyridamole (DIP)) was also investigated. The multifunctional polymeric nanocapsules could be used as a promising smart drug delivery system with magnetic-targeted function.