Ascidian-inspired aciduric hydrogels with high stretchability and adhesiveness promote gastric hemostasis and wound healing

Adhesives for gastric hemorrhage are of great clinical significance. However, it remains a major challenge in clinics due to its poor stability under acidic environments and low adhesion to wet tissues. Herein, inspired by the high adhesiveness of the ascidian secretory protein, we designed a series of aciduric bionic hydrogel adhesives (PDTAs) based on poly(γ-glutamic acid) (γ-PGA) and tannic acid (TA). The formation of hydrogel adhesives was attributed to the abundant hydrogen bonds between amide groups of PGA-DA and polyphenol groups of TA. These hydrogel adhesives exhibited enhanced wet tissue adhesion (400%), higher stretchability (800% elongation), and aciduric stability (7 days) compared with commercial fibrin glue. Rodent wound models indicated that the hydrogel adhesives demonstrated significant healing promotion due to ameliorating collagen deposition and angiogenesis. These hydrogel adhesives show great potential in treating gastric hemorrhages and promoting wound healing.