Preparation and biodegradation of nanogels as carriers for carbohydrate drugs

POLY 221

Daniel J. Siegwart, danielsiegwart@cmu.edu, Jung Kwon Oh, jkoh@andrew.cmu.edu, and Krzysztof Matyjaszewski, km3b@andrew.cmu.edu. Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213
Stable nanogels entrapped with different amounts of rhodamine B isothiocyanate-dextran (RITC-Dx) as a model water-soluble biomacromolecular drugs were successfully prepared using atom transfer radical polymerization (ATRP) in cyclohexane inverse miniemulsion in the presence of RITC-Dx and a disulfide-functionalized crosslinker. The extent of incorporation of RITC-Dx to nanogels upon degradation of nanogels was characterized by UV-Vis spectroscopy. The loading efficiency of RITC-Dx to nanogels exceeded 80%. Significant amounts of these nanogels (over 95%) were degraded into polymeric sols using water-soluble reducing agents, including dithiothreitol and glutathione. Release experiments demonstrated that degradation can trigger controllable release of encapsulated carbohydrate drugs. The released carbohydrate biomolecules from nanogels upon degradation were able to specifically interact with Concavalin A in water. These results suggest that nanogels could deliver carbohydrate drugs upon degradation in the presence of biocompatible glutathione to bind to pathogens based on lectins