Macromolecular release using thermoresponsive anionic hydrogels

CHED 799

Koko Takatori, ktakator@wellesley.edu and Nolan T. Flynn, nflynn@wellesley.edu. Department of Chemistry, Wellesley College, 21 Wellesley College Road, Unit 3917, Wellesley, MA 02481
Poly(N-isopropylacrylamide) (p(NIPAm)) hydrogels are thermoresponsive polymer networks with reversible swelling capacities. Because of this property, p(NIPAm) hydrogels are being studied as potential drug delivery vehicles. We have created anionic thermoresponsive hydrogels by copolymerizing NIPAm with acrylic acid (AAc). Gold nanostructures are then grown within the p(NIPAm-co-AAc) hydrogel matrices, which can alter the phase transition temperature for hydrogels, depending on the crosslinking agent used during synthesis. These p(NIPAm-co-AAc) hydrogels are then loaded with one of several types of model drugs of different molecule weights and charges. Spectroscopic methods are used to monitor the diffusion of the model drugs from the hydrogel matrices. Parameters affecting release, such as size and charge state of the model drug, release temperature, and identity and concentration of hydrogel crosslinking agent, were investigated. Results from these studies will be presented.