Professor Liu Wenguang’s team from Tianjin University reports development of a Janus hydrogel wet adhesive for internal tissue repair and anti-postoperative adhesion.

This novel adhesive has two sides that show strikingly distinct adhesive and non-adhesive properties. One side is capable of sticking to various soft wet tissues while the other side is totally non-adhesive, efficiently preventing postoperative adhesion. The Janus hydrogel wet adhesive can be completely degraded and absorbed by the body within 14 days. It provides a promising alternative to surgical stitches due to simplicity of deployment and saving of time.

When internal organs suffer great trauma and need stitching up, surgical suture (commonly called stitches) is used to hold body tissues together. However, the stitching process may cause secondary damage to the tissue since it is time-consuming and difficult. To address this concern, tissue adhesives are considered a good replacement for surgical suture. However, most of the reported adhesives have double-sided adhesion, which allows undesired indiscriminate post-surgical adhesion. Clinically, post-operative adhesion can cause severe consequences including chronic pelvic pain, ileus and infertility.

To date, a variety of biomaterials have been reported to prevent post-surgical adhesion, but they cannot replace surgical sutures for tissue repair because they don’t adhere to wet tissues. Therefore, it is of clinical significance to design and construct a bioadhesive that can robustly bond wet tissues and prevent undesired post-surgical tissue adhesion.

Prof. Liu’s team used a one-sided dipping method to create a negatively charged carboxyl-containing hydrogel with a cationic oligosaccharide and form a novel Janus hydrogel wet adhesive.

The Janus hydrogel has been tested in rabbits as a replacement of traditional sutures to treat gastric perforation. Animal experiment outcomes reveal that one side of the Janus hydrogel is firmly glued to the stomach tissue, while the other side, facing outward, can efficiently prevent postoperative adhesion.

The research results have been published in Advanced Functional Materials.