Blood-repellence as an answer to the vulnerability of medical implants

Two disciplines, biomedical engineering and materials science have combined to produce a material that is compatible with blood.

Colorado State UniversityBlood, plasma and water droplets beading on a superomniphobic surface. CSU researchers have created a superhemophobic titanium surface, repellent to blood, that has potential applications for biocompatible medical devices.

Medical implants such as stents, catheters and tubing can introduce a risk of blood clots and infection so researchers are designing blood repellent titanium.

Researchers at Colorado State University studied various types of titanium surfaces, including different textures and chemistries, comparing the extent of platelet adhesion and activation. They found that fluorinated nanotubes offered the best protection against clotting – in other words it becomes superhemophobic.

Biomedical scientists often use materials “philic” (having affinity) to blood to make them biologically compatible.

Colorado State UniversityFluorinated nanotubes provided the best superhemophobic surface in the researchers’ experiments.

Arun Kota, assistant professor of mechanical engineering and biomedical engineering at CSU, said: “What we are doing is the exact opposite.

“We are taking a material that blood hates to come in contact with, in order to make it compatible with blood.

“The key innovation is that the surface is so repellent that blood is tricked into believing there’s virtually no foreign material there at all.”

Kota, whose expertise is in superomniphobic materials that repel liquid, worked with Ketul Popat, an associate professor who works with tissue engineering and bio-compatible materials. Starting with sheets of titanium, commonly used for medical devices, chemically altered surfaces were grown acting as barriers between the titanium and blood.

The scientists said that growing a surface and testing it in the lab is only the beginning. The study was published in Advanced Healthcare Materials.