Swelling and Mechanical Properties of a Temperature‐Sensitive Dextran Hydrogel and its Bioseparation Applications

A series of temperature-sensitive dextran hydrogels (poly(NIPA-co-GMA-Dex)) were synthesized by the copolymerization of glycidyl methacrylate-derivatized dextran (GMA-Dex) and N-isopropylacrylamide (NIPA) in aqueous solution. Their swelling and mechanical properties and bioseparation behaviors were studied. It is found that poly(NIPA-co-GMA-Dex) hydrogels simultaneously exhibit much better swelling and mechanical properties. The interactions between poly(NIPA-co-GMA-Dex) hydrogels and sodium dodecylsulfate (SDS), Rutin, and DL-α-alanine were different because of their different hydrophobic nature, polarity, and molecular structure, and obviously depend on the temperature: the mechanism is discussed. In addition, using poly(NIPA-co-GMA-Dex) hydrogels as the absorbents, gel-extraction separation experiments of dextran and BSA solutions showed that the separation ability of poly(NIPA-co-GMA-Dex) hydrogels obviously increased upon reaching the LCST.