Hydrogel Bioadhesives with Extreme Acid‐Tolerance for Gastric Perforation Repairing

Abstract

Hydrogel bioadhesives have emerged as one of the most promising alternatives to sutures and staples for wound sealing and repairing, owing to their unique advantages in biocompatibility, mechanical compliance, and minimally invasive manipulation. However, only a few hydrogel bioadhesives have been successfully used for gastric perforation repair, due to their undesirable swelling when in direct contact with extremely acidic gastric fluids, and are thereby accompanied by a gradually deteriorating adhesion performance. Herein, an acid-tolerant hydrogel (ATGel) bioadhesive is developed, which integrates two distinct components, an acid-tolerant hydrogel substrate and an adhesive polymer brush layer. The ATGel bioadhesive can form instant, atraumatic, fluid-tight, and sutureless sealing of gastric perforation, and enable robust biointerfaces in direct contact with gastric fluids, addressing the key limitations with sutures and commercially-available tissue adhesives. Moreover, in vivo investigation on gastric perforation of rat model validates the proposed acid-tolerant bioadhesion, and identifies the mechanisms for accelerated gastric perforation repair through alleviated inflammation, which suppresses fibrosis and enhances angiogenesis.

Tough Wet Adhesion of Hydrogen-Bond-Based Hydrogel with On-Demand Debonding and Efficient Hemostasis

“…The instability of hydrogen bonding in an aqueous environment makes it challenging to enhance the strength and adhesion of hydrogels using hydrogen bonding . To solve this problem, complementary multiple hydrogen bonds and electrostatic interaction are proposed to enhance the wet adhesion of hydrogels. − …”

Chitosan Grafted Poly (Ethylene Glycol) Methyl Ether Acrylate Particulate Hydrogels for Drug Delivery Applications

“…Hydrogel nanoparticles are promising nanomaterials due to advantages such as targeting, decreasing drug dose, the possibility of maintaining a desired therapeutic concentration, and low toxicity effects [ 2 ]. Moreover, a hydrogel is a polymer three-dimensional network, capable of capturing large amounts of water or active principles due to its hydrophilic structure, presenting excellent properties such as a porous structure, sensitivity to different environmental factors (pH, temperature, light), biocompatibility, and the similarity of their physical properties to natural tissue, which led to its use as support material in tissue engineering [ 3 , 4 , 5 , 6 , 7 , 8 ].…”

Brush-Modified Hydrogels: Preparations, Properties, and Applications

“…(e) Schematic diagram of ATGels for sealing gastric perforation. [Reproduced with permission from ref . Copyright 2022, Wiley–VCH GmbH.…”

“…Chen et al integrated an adhesive poly(acrylic acid-co-Nhydroxysuccinimide acrylate ester (poly(AA-NHS)) brush layer with acid-tolerant poly(2-hydroxyethyl methacrylate-co-Nvinylpyrrolidone (poly(HEMA-NVP)) hydrogel substrate to develop an acid-tolerant hydrogel (ATGel) via a dry crosslinking mechanism (Figure 19e). 178 The collaborative contribution from hydrogen bonds, electrostatic noncovalent interactions, and NHS-ester cross-linking between poly(AA-NHS) and amine moieties from tissue provided an instant and tough bioadhesion between the hydrogel bioadhesive and tissue, and showed high efficacy for gastric perforation repairing. The combinations of ATGels bioadhesives and delivery techniques can expedite the development of noninvasive treatment for gastric perforation repairing in diverse clinical settings.…”