To enhance the drug uptake and release capacity of silicone rubber (SR), N-
isopropylacrylamide (NIPA) hydrogel particles have been incorporated into a
SR membrane. The NIPA particles were thoroughly blended with uncured SR wi
th a certain ratio at room temperature. The mixture was then cast in a Petr
i dish to 1 mm thickness and cured 10 hours at 90 degreesC. The SR/NIPA com
posite gel can absorb water approximately equal to its dry weight. Brillian
t blue, used as a mock drug, was loaded into the composite gel. Drug releas
e increased exponentially to a final value that is temperature dependent: l
ow at T> =34 degreesC, and high at T< 34<degrees>C. This finding is because
the hydrophobicity of NIPA changes with temperature. Pulsed release in res
ponse to temperature switching between 20 and 39 degreesC has been achieved
. Drug uptake and release capability strongly depends upon the structure of
the composite gel. The optimal range of NIPA composition is between 75 and
87% by volume. In the cited range, the NIPA particles form an interconnect
ed network that provides a channel for diffusion of drug solution. The SR/N
IPA composite gel has promising attributes as a wound dressing and other us
es.