The chemistry and engineering of polymeric hydrogel adhesives for wound closure: a tutorial

Abstract

The closure and repair of wounds after traumatic or surgical injury is of significant clinical and research importance. While sutures remain the common wound closure technique, they have many disadvantages. Consequently, polymeric hydrogel adhesives have emerged as essential materials for wound management and repair because of their tunable chemical and physical properties, which enable them to adhere or stick to tissues, possess sufficient mechanical strength to stay intact and be subsequently removed, provide complete wound occlusion, and act as a barrier to bacterial infection. Moreover, these materials absorb wound exudates and keep the wound moist for faster healing. This tutorial review summarizes the key chemical features that enabled the development and use of polymeric hydrogels as wound adhesives, sealants, and hemostats, their design requirements, synthetic routes, determination of properties, and the tests needed to evaluate their performances. This tutorial review is a reference and a starting point for scientists and clinicians working or interested in the field of wound management and, importantly, for the general audience who is interested in polymers for medical applications.

Enhanced tissue adhesiveness of injectable gelatin hydrogels through dual catalytic activity of horseradish peroxidase

“…The gelation time was determined at the point which G 0 and G 00 cross over. [3] All samples were tested in triplicate for each experimental condition.…”

“…[1] However, strategies to improve adhesive quality and the demand for new adhesives require continuous development to overcome the disadvantages of currently used commercial adhesives and fulfill all the requirements of clinical use, such as facile operation, biocompatible and degradable materials, biological integration, and strong tissue-tissue or tissueimplant attachment. [1,3] For example, cyanoacrylate has fast and strong adhesion, but cytotoxicity can be induced by the release of degradation products (i.e., aldehyde), and it lacks flexibility, especially for closing incisions in soft tissues or those with large size. Although polyethylene glycol-based adhesives are inert and nontoxic, they have poor mechanical properties and act as a barrier to tissue ingrowth and wound healing.…”

Self‐Adjustable Adhesion of Polyampholyte Hydrogels

“…[12] Two ribbons of hydrogels (length l × width w= 75 ×25 mm 2 ) were cut by scalpel. They were brought into contact with a piece of PA hydrogel (l×w×h=20×25×1.7 mm 3 ), which form a junction contact area of 5 cm 2 ( Figure 3A).…”

“…[10,11] But these approaches have limitations in practical applications, such as lengthy and complicated way of processing, lack of water resistivity and universality, inability in non-residual removal, etc. [12] The clue to develop adhesives working for hydrogels and biological tissues hides in nature.Bacteria cells, ubiquitous in environment, can attach with almost any surfaces including human tissues, regardless the diversity in the surface chemistry. The self-adjustable capability of the extracellular polymeric matrix (EPM) of bacteria cells has made this possible.…”

“…[10,11] But these approaches have limitations in practical applications, such as lengthy and complicated way of processing, lack of water resistivity and universality, inability in non-residual removal, etc. [12] The clue to develop adhesives working for hydrogels and biological tissues hides in nature.…”