Stimuli-Responsive Hydrogels and Their Applications in Drug Delivery Systems

STIMULI-RESPONSIVE HYDROGELS AND THEIR APPLICATIONS IN DRUG DELIVERY SYSTEMS 

Poly(N-isopropylacrylamide) Hydrogels for Thermo-Responsive Drug Delivery 

For PIPAAm hydrogels, a large temperature increase originating below the polymer transition temperature of 32°C induces an outside-in shrinking response in the gel thermal transfer and polymer mass transfer kinetics compete for the determining of the polymer phase behavior. For this condition, the result is the formation of a dense shrunken collapsed polymer layer at the gel-water interface (a skin layer). These dehydrated polymer skin layers on the surface of shrunken PIPAAm hydrogels prevent even water molecules from 

PIPAAm-grafted PIPAAm cross-linked hydrogel 

Thermo-Responsive Sol-to-Gel Transitions and Exploitation for Injectable Drug Delivery 

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