(397f) Synthesis and Characterization of Magnetic Biodegradable Poly(D,L-lactide-co-glycolide) Nanocapsules

The objective of this study was to develop biodegradable/biocompatible polymer-coated magnetic nanocapsules for potential biomedical applications. Air-filled magnetic nanocapsules were prepared by an ultrasound emulsification technique and multiple emulsion-solvent evaporation method utilizing highly concentrated magnetic Fe₃O₄ nanoparticles and poly(D,L lactide-co-glycolide) (PLGA). Hydrophilic and hydrophobic Fe₃O₄ nanoparticles separately modified with monolayer and bilayer of oleic acid, exhibiting good miscibility in inter water solution and biopolymer solution, and were induced to the core and shell area of PLGA nanocapsules during the procedure of emulsification. Air-filled nanocapsules with magnetic Fe₃O₄ nanoparticles embedded were obtained with a mean diameter of about 700 nm. We characterized these nanocapsules in terms of external morphology, microstructure, size and magnetite content and distribution within the nanostructures. Both the core-embedded and shell-embedded magnetic nanocapsules showed efficient contrast in vitro for ultrasound imaging, and suitable as a potential platform for the design of magnetically guided drug delivery and other in vivo biomagnetic applications.