Thermally Driven Hydrogel Actuator for Controllable Flow Rate Pump in Long-Term Drug Delivery

摘要: ‘Smart’hydrogelscanchangetheirvolumebyalargefractioninresponsetomanystimuli,suchastemperature,pH,ionsconcentration,solventcompositionandlightirradiation.Thisenvironmental sensitivity plays an important role in achieving new technological andscientific applications.Hydrogels used as osmotic pumps were introduced the 1970s. They allowed thedevelopment of drug delivery systems, such those for therapies thegastrointestinal tract. Easy to regulate long-term devices with a very simple mechanicaldesign could be commercially convenient respect using complex electro-mechanical systems.In this chapter use thermally activated hydrogel actuator realization oflong-term systems able control flow rate following defined tasksis investigated. In first part, materialproperties thethermally sensitive hydrogel,whose network is constituted by cross-linked poly(vinyl-methyl-ether) (PVME) mole-cules, are outlined; dynamic properties designed system usingsuch driving then derived.31st January 2009 18:15 Wiley/ETA Page 89 c04