Crosslinking Trends in Multicomponent Hydrogels for Biomedical Applications.

Multicomponent-based hydrogels are well established candidates for biomedical applications. However, certain aspects of multicomponent systems, e.g., crosslinking, structural binding, network formation, proteins/drug incorporation, etc., are challenging aspects to modern biomedical research. The types of crosslinking and network formation are crucial for the effective combination of multiple component systems. The creation of a complex system in the overall structure and the crosslinking efficiency of different polymeric chains in an organized fashion are crucially important, especially when the materials are for biomedical applications. Therefore, the engineering of hydrogel has to be, succinctly understood, carefully formulated, and expertly designed. The different crosslinking methods in use, hydrogen bonding, electrostatic interaction, coordination bonding, and self-assembly. The formations of double, triple, and multiple networks, are well established. A systematic study of the crosslinking mechanisms in multicomponent systems, in terms of the crosslinking types, network formation, intramolecular bonds between different structural units, and their potentials for biomedical applications, is lacking and therefore, these aspects require investigations. To this end, the present review, focuses on the recent advances in areas of the physical, chemical, and enzymatic crosslinking methods that are often, employed for the designing of multicomponent hydrogels.