Response behavior of ion-sensitive hydrogel based on crown ether

A type of poly(N-isopropylacrylamide) (PNIPAM) hydrogel with specific ion-sensitivity originating from crown ether unit is synthesized. The impacts of crown ether unit on temperature-sensitivity and ion-sensitivity of hydrogel are investigated. The result showed that crown ether units in the hydrogel network contributed to the ion response though they would reduce temperature-sensitivity of the hydrogel compared with traditional PNIPAM. Furthermore, the thermo-sensitivity and ion-recognition behaviors of the hydrogel are detailedly demonstrated which showed its potential as a promising candidate material for environment inspection, sensors and drug delivery systems.