Recent advances in supramolecular hydrogels for biomedical applications

Abstract

Supramolecular hydrogels held together by non-covalent interactions such as electrostatics, hydrogen bonding, and hydrophobic forces are among the most promising soft material platforms for modern biomedical applications. By virtue of their inherent reversibility and dynamism, they respond well to environmental stimuli and biochemical cues and can dissipate mechanical energy effectively. These important features are well suited for cell culture, tissue engineering, on-demand controlled release of therapeutics, tissue adhesion, and molecular sensing and as artificial gel substitutes in organs (e.g., vitreous humour and synovial fluids), which are not easily achieved by permanently cross-linked covalent hydrogels. Consequently, supramolecular hydrogels have grown in popularity and have witnessed rapid development for biomedical applications in recent years. Through the numerous applications and exciting advances during the last five years discussed in this mini-review, we highlight how the supramolecular interactions enabling gel formation also translates to their bulk material properties and resulting biomedical applications. Owing to their versatility and ease of ‘bottom-up’ engineering from the molecular level, supramolecular hydrogels are poised to offer a wide range of biomedical solutions to modern societal problems, including but not limited to wound healing, development of artificial tissues, cell therapies, and anticancer treatment. Keywords: Physically-crosslinked hydrogels, Hydrophobic interactions, Hydrogen bonding, Ionic interactions, Inclusion complexes