Zwitterion coating could prevent blood clots on medical implants

Proteins in blood can cling to the sides of the medical implants, building up over time and forming a blood clot. Often this requires invasive surgery to remove or replace the implant.

“Medical implants are constantly under pressure to perform in the human body. A heart valve is constantly under high pressure to pump blood, opening and closing half a billion times over 10 years,” said Dr Sina Naficy, who leads a research team developing heart valves that are more resistant to blood clots.

“The current average lifespan of existing heart valve implants is less than 10 years and there is always a risk of them degrading or complications occurring. By using Zwitterion coated materials, we aim to decrease the risk of blood clots and increase the lifespan of heart valves and other medical implants,” said Dr Naficy, from the University’s School of Chemical and Biomedical Engineering, Faculty of Engineering.

Zwitterions are molecules with positively and negatively charged groups, resulting in a neutral overall charge. They are very effective at forming bonds with water molecules, and are in human cells as part of the cell membrane. They create a thin layer of water and make sure blood and other proteins travel through the heart and other organs without sticking to other surfaces.