Intelligent design and application of molecular recognition hydrogels in tissue engineering

Molecular recognition hydrogels are functional materials that form three-dimensional network structures through molecular-specific binding, such as antigen-antibody and ligand-receptor interactions. They exhibit excellent biocompatibility, tunable mechanical properties, and dynamic responsiveness. Furthermore, these hydrogels can simulate the microenvironment of the natural extracellular matrix and precisely regulate cell behavior, thereby broadening their application in tissue engineering. Herein, we review the definition of molecular recognition hydrogels; available crosslinking strategies, including physical, chemical, and biological crosslinking; and examples of representative systems, such as DNA hydrogels and heparin-binding protein hydrogels. We also summarize the latest research on molecular recognition hydrogels for drug delivery, biosensing, and tissue repair and regeneration (including bone, cartilage, skin, heart, and neural tissues). In addition, we discuss the challenges (such as stability and targeting) and future development directions in this field, providing new ideas for precision and personalized treatments in tissue engineering.