Strong, Chemically Stable, and Enzymatically On‐Demand Detachable Hydrogel Adhesion Using Protein Crosslink

Abstract

Achieving strong adhesion between hydrogels and diverse materials is greatly significant for emerging technologies yet remains challenging. Existing methods using non‐covalent bonds have limited pH and ion stability, while those using covalent bonds typically lack on‐demand detachment capability, limiting their applications. In this study, a general strategy of covalent bond‐based and detachable adhesion by incorporating amine‐rich proteins in various hydrogels and inducing the interfacial crosslinking of the hydrogels using a protein‐crosslinking agent is demonstrated. The protein crosslink offers topological adhesion and can reach a strong adhesion energy of ≈750 J m−2. The chemistry of the adhesion is characterized and that the inclusion of proteins inside the hydrogels does not alter the hydrogels’ properties is shown. The adhesion remains intact after treating the adhered hydrogels with various pH solutions and ions, even at an elevated temperature. The detachment is triggered by treating proteinase solution at the bonding front, causing the digestion of proteins, thus breaking up the interfacial crosslink network. In addition, that this approach can be used to adhere hydrogels to diverse dry surfaces, including glass, elastomers and plastics, is shown. The stable chemistry of protein crosslinks opens the door for various applications in a wide range of chemical environments.

MnO2 Decorated Metal‐Organic Framework‐Based Hydrogel Relieving Tumor Hypoxia for Enhanced Photodynamic Therapy

“…However, the clinical application of nMOFs is limited by their low in vivo stability and cumbersome post-modification processes. [16] Injectable hydrogels offer an attractive option for local cancer therapy due to their unique properties [17] such as a 3D network structure, hydrophilicity, and the ability to deliver drugs, [18] proteins, [19] and nanoparticles [20] directly to the tumor site. Chitosan (CS) is an appealing hydrogel monomer due to its excellent biocompatibility, biodegradability, and non-immunogenicity.…”