Biomolecule-sensitive hydrogels.

Stimuli-sensitive hydrogels have attracted considerable attention as intelligent materials in the biochemical and biomedical fields, since they can sense environmental changes and induce structural changes by themselves. In particular, biomolecule-sensitive hydrogels that undergo swelling changes in response to specific biomolecules have become increasingly important because of their potential applications in the development of biomaterials and drug delivery systems. This article provides an overview of the important and historical research regarding the synthesis and applications of glucose-sensitive hydrogels which exhibit swelling changes in response to glucose concentration. Enzymatically degradable hydrogels and antigen-sensitive hydrogels are also described in detail as protein-sensitive hydrogels that can respond to larger biomolecules. The synthetic strategies of other biomolecule-sensitive hydrogels are summarized on the basis of molecular imprinting and specific interaction. The biomolecule-sensitive hydrogels reviewed in this paper are expected to contribute significantly to the exploration and development of newer generations of intelligent biomaterials and self-regulated drug delivery systems.