A new water-resistant material could provide another tool for medical device designers.
Boston University and MIT researchers in the journal Nature describe a material with a novel surface structure that provides very high levels of water resistance, or hydrophobicity.
The surface accomplished this feat by minimizing the amount of time that a liquid can maintain contact with it.
The novel surface features extremely small ridges that rise above the surface plane by 0.1 millimeters. When water or other fluids come in contact with the surface, droplets recoil away in an asymmetric pattern, allowing them to split into smaller liquid droplets. Compared to a globule of liquid, these smaller droplets can travel at a higher speed.
By breaking down liquid globules, the researchers noted that the surface structure can reduce the amount of time that water remains in contact by 37%.
Hydrophobic materials are used by the medical device industry for a variety of uses. In particular, hydrophobic surfaces are used to control contamination. For example, microporous vents are often created with hydrophobic materials. Through the use of hydrophobic microporous vents, manufacturers can design surfaces that allow for gas exchange while preventing the movement of liquids. This can include liquids like emulsions, blood and urine.
Common medical devices that feature microporous materials include IV line vents, urine bags, ostomy bags and transducer protectors.
Source: www.qmed.com; December 3, 2013.