An illustration of the core-sheath structure and mechano-electrical conversion mechanism of the bioabsorbable electrical stimulation suture (BioES-suture). Credit: Zhouquan Sun and Chengyi Hou

A team of chemical fiber and polymer material researchers in China has found that the use of internally produced, electrically charged sutures can speed up the healing process after surgery in rats. In their study published in Nature Communications, the group developed a type of suture that generates its own electricity while inside the body and tested it in a lab setting and in live rats.

Prior research has shown that the application of electricity to wounds can speed up healing—it attracts fibroblasts, which are a major part of the healing process. Prior research has also shown that applying electrical current to conductive sutures can promote healing. But these sutures require an external power source or a bulky battery. In this new effort, the research team found a way to power sutures using interactions between the sutures and surrounding tissue.

The sutures were made using biodegradable polymers and magnesium, both of which can be absorbed safely by the body over time.

When muscles and other tissue around the site of a surgical procedure move, the middle layer of the sutures rubs against the outer layer, transferring electrons. The resulting electricity moves through the rest of the suture, stimulating the tissue that has been sewn together.

The sutures are just 350 microns, the size needed for closing wounds. Because they are biodegradable, doctors would not have to remove them.

• An illustration of wound sealing and healing functions offered by the bioabsorbable electrical stimulation suture (BioES-suture). Credit: Zhouquan Sun and Chengyi Hou
• A photograph of the bioabsorbable electrical stimulation suture (BioES-suture). Credit: Zhouquan Sun and Chengyi Hou

During lab experiments, the sutures were found to be capable of generating 2.3 volts during normal activity. When used with live tissue, the sutures were found to speed up healing by 50% compared to non-electrified sutures. They also resulted in lower bacterial levels, even when standard disinfectants were not used.

The research team next tested their sutures on rats and observed speedier recovery and fewer infections. They plan to test their sutures in larger animals before eventually moving on to trials in humans.