Rapid pH/temperature-responsive cationic hydrogels with dual stimuli-sensitive grafted side chains

摘要: Abstract Dual temperature- and pH-sensitive comb-type grafted cationic hydrogels are successfully synthesized by grafting polymeric chains with freely mobile ends, which composed of both N -isopropylacrylamide (NIPAM) segments , -dimethylamino ethyl methacrylate (DMAEMA) segments, onto the backbone crosslinked poly(NIPAM- co -DMAEMA) networks. Equilibrium dynamic swelling/deswelling properties prepared responding to pH and/or temperature investigated. The demonstrate a lower critical solution (LCST) at about 34 °C p K value 7.3. At temperature, swelling degree rate hydrogel larger than those normal-type hydrogel. exhibits more rapid deswelling that in response jump from 2.0 11.0 fixed temperature. volume changes acute series buffer solutions an abrupt increase environmental 18 °C higher LCST. show quite fast shrinking behaviors simultaneous dual stimuli. Drug-release vitro is carried out when changed synchronously. results model drug Vitamin B 12 released much rapidly proposed temperature/pH-sensitive this study may find various potential applications, e.g. for fabricating rapid-response smart sensors, actuators, chemical/drug carriers so on.