A study published on Wednesday in ACS Nano, a journal of American Chemistry Society, reported a kind of surface coating that can repel everything, such as bacteria, viruses and living cells, but can be modified to permit beneficial exceptions.
The new discovery lends promises to many medical applications, making it possible for implants such as vascular grafts, replacement heart valves and artificial joints to bond to the body without risk of infection or blood clotting.
It may also works to reduce false positives and negatives in medical tests by eliminating interference from non-target elements in blood and urine.
"It was a huge achievement to have completely repellent surfaces, but to maximize the benefits of such surfaces, we needed to create a selective door that would allow beneficial elements to bond with those surfaces," said Tohid Didar with McMaster University and the senior author of the paper.
By designing the surface to permit adhesion only with heart tissue cells, the researchers are making it possible for the body to integrate the new valve naturally, avoiding the complications of rejection.
The same would be true for other implants, such as artificial joints and stents used to open blood vessels, according to the study.
Outside the body, selectively designed repellent surfaces could make diagnostic tests much more accurate by allowing only the particular target of a test, for example, a virus, bacterium or cancer cell, to stick to the biosensor that is looking for it, making it an advantage given the challenges of testing in complex fluids such as blood and urine.
