ABSTRACT
Thermo-sensitive hydrogels were prepared by grafting N-isopropylacrylamide (NIPAAm) onto chitosan and dextran. The grafting reactions were performed during variable periods of time and different films were obtained. To prepare a drug-delivery system for sublingual delivery of Ondansetron™, this drug was entrapped in the films. Elemental analysis results showed that the amount of poly(NIPAAm) in the final films increased with reaction time, influencing their lower critical solution temperature and swelling behavior. Also, drug release profile depended on grafting extension as well as on the temperature, as the release of Ondansetron™ presented a more sustained-like profile at physiologic temperature.
GRAPHICAL ABSTRACT
Acknowledgments
José Filipe Almeida (SFRH/BD/19707/2004), Paula Ferreira (SFRH/BPD/86338/2012), and Patrícia Alves (SFRH/BPD/69410/2010) gratefully acknowledge FCT for the financial support.