While medical implants such as stents, catheters and various forms of inserted tubing provide medical benefits to many patients, these implanted devices pose great issues to a vast array of those with them. More specifically implanted devices increase risks of blood clots and infections in patients who need them.
To solve this compounding issue, engineers from the Colorado State University (CSU) have developed a “superhemophobic” titanium surface that repels blood. As such, this new material could act as the core substance used in future medical implants placed in patients’ bodies.
Bridging the gap between biomedical engineering and materials science, these engineers used a method of unorthodox thinking to devise a contraption that would be less likely to be rejected by the human body. The project was published in Advanced Healthcare Materials and is a result of a cross-disciplinary collaboration between Arun Kota, assistant professor of mechanical engineers and biomedical engineering, and Ketul Popat, an associate professor in both departments.
Kota’s expertise comes from his work with “superomniphobic” substances that preferentially avoid all liquids. This work, combined with Popat’s knowledge of tissue engineering and materials that are accepted by the human body culminated in the radically new concept of titanium-based implants.
The combined efforts of their research labs laid the groundwork for material surfaces that acted as barriers between titanium and blood which minimized blood platelet attachment: the body’s method for rejecting unfamilar materials and a precursor to blood clots.
The unique idea behind the titanium-based implants lies in the fact that the team of engineers seem to employ an almost backwards methodology toward tackling the problem.
While many scientists working on the issue think using hemophilic materials, materials that preferentially come in contact with blood, is best, the engineers from CSU think the contrary. By using materials that would rather avoid blood, they are treated by blood as if they simply do not exist and are not the target of blood clotting.
“We are taking a material that blood hates to come in contact with, in order to make it compatible with blood,” Kota said.
According to Popat, unwanted interaction between blood and foreign surfaces is unfortunately a longstanding problem in the medical field. Clots that arise from implants can ultimately be detrimental to a patient’s overall health and often require the use of blood-thinning medications that are simply not foolproof.
“The reason blood clots is because it finds cells in the blood to go to and attach,” Popat said. “Normally, blood flows in vessels. If we can design materials where blood barely contacts the surface, there is virtually no chance of clotting, which is a coordinated set of events. Here, we’re targeting the prevention of the first set of events.”
The team of engineers has used a wide scope of chemically-treated titanium surfaces and has found that fluorinated nanotubes prevent clotting best. The team hopes to continue their efforts towards optimizing such a surface on the titanium implants that can solve the issue complicating the treatment of those who require medical implants.
