Fabrication of strong hydrogen-bonding induced coacervate adhesive hydrogels with antibacterial and hemostatic activities

In this work, a biocompatible poly(N-hydroxyethyl acrylamide) (PHEAA) polymer with hydrogen bonding acceptors and donors in its side chains is prepared and mixed with tannic acid (TA) to form a supramolecular coacervate hydrogel (TAHE) due to multiple hydrogen-bonding interactions between TA and PHEAA. The coacervate TAHE hydrogel exhibits not only self-healing and antibacterial properties, but also strong adhesion to various substrates, with average adhesion strengths of 722 kPa, 522 kPa, 484 kPa, and 322 kPa to the substrates of iron, PMMA, ceramics, and glass, respectively. Notably, the hydrogel reformed by the rehydration of freeze-dried and ground TAHE hydrogel powder retains the initial adhesive performance and exhibits an excellent hemostatic ability. This novel adhesive hydrogel holds great potential as an adhesive hemostatic material for self-rescue in emergency situations.