Catechol-modified wet-adhesive hydrogel for the repair of the gastric epithelium

Gastric perforation, which may be caused by damage to the gastric epithelium, can lead to the entry of food or gastric acid in the stomach into the peritoneum, causing diseases such as peritonitis and sepsis. In severe cases, it can lead to septic shock and pose a threat to life. Developing and preparing a material that has adhesiveness in a wet environment such as the surface of the stomach is a challenge. Therefore, we have successfully prepared a hydrogel membrane with wet adhesiveness. This hydrogel membrane is composed of glutaraldehyde-crosslinked polyvinyl alcohol (PVA) hydrogel modified by 3,4-dihydroxyphenylalanine (DOPA). The side chains of PVA molecules modified with DOPA achieve wet adhesion through the formation of hydrogen bonds between the catechol groups and the surface of the tissue substrate. It is used for suture-free repair of damaged gastric epithelium. According to the results of mechanical experiments, its wet adhesion lap shear strength to gastric tissue reaches 34.8 kPa, and the peeling strength reaches 24.5 kPa. The results of in vitro cell experiments show that the hydrogel has good biocompatibility. The hydrogel prepared by this simple method demonstrates adaptability to the gastric environment, making it promising for applications in gastric wound repair.