A Rapidly Self-Healing Host-Guest Supramolecular Hydrogel with High Mechanical Strength and Excellent Biocompatibility

Abstract

<p class="first" id="P1">It is still a challenge to achieve both excellent mechanical strength and biocompatibility in hydrogels. Here we exploited two interactions to form a novel biocompatible, slicing-resistant and self-healing hydrogel. One is the molecular host-guest recognition between a host (isocyanatoethyl acrylate-modified β-cyclodextrin, β-CD-AOI ₂) and a guest (2-(2-(2-(2-(Adamantyl-1-oxy)ethoxy)ethoxy) ethoxy)ethanol acrylate, A-TEG-Ad) to form novel “three-arm” host-guest supramolecules (HGSMs). Another is the covalent bonding between HGSMs (achieved by UV-initiated polymerization) to form a strong crosslinking in the hydrogel. The host-guest interaction enabled the hydrogel to become rapidly self-healing; cutting it formed fresh surfaces with dangling host and guest molecules (due to the breaking of host-guest recognition), which rapidly recognized each other again to recombine the cut surfaces and thus heal the hydrogel. The smart hydrogels hold promise for use as biomaterials in soft tissue repair. </p><p id="P2">A novel “three-arm” host-guest supramolecular monomer is designed to avoid steric hindrance effect, enabling more efficient host-guest inclusion. The monomer is further polymerized into hydrogels that are not only strong, slicing resistant and capable of rapid self-healing, but also biocompatible. The hydrogels hold promise for potential use as biomedical materials in regenerative medicine. </p><p id="P3"> <div class="figure-container so-text-align-c"> <img alt="" class="figure" src="/document_file/252eee1a-7915-47d7-80f1-edba213ed3a1/PubMedCentral/image/nihms-1503561-f0001.jpg"/> </div> </p>