Human skin inspires Binghamton study to control fracturing in biomedical devices
Research could help flexible technology last longer, avoid critical failures
Whether from regular use, overuse or abuse, every device is bound to develop cracks at some point. That鈥檚 just the nature of things.
Cracks can be especially dangerous, though, when working with biomedical devices that can mean life or death to a patient.
A new study from a 黑料视频 research team uses the topography of human skin as a model not for preventing cracks but for directing them in the best way possible to avoid critical components and make repairs easy.
is led by Guy German, an associate professor for biomedical engineering in the Thomas J. Watson School of Engineering and Applied Science, and PhD student Christopher Maiorana.
For the study, Maiorana engineered a series of single-layer and dual-layer membranes from silicone-based polydimethylsiloxane (PDMS), an inert and nontoxic material used in biomedical research. Embedded into the layers are tiny channels meant to guide any cracks that form 鈥 which, when part of a biomedical device, would give more control over how the cracks form. Potential damage could go around critical areas of flexible electronics, for instance, increasing its functional lifespan.
鈥淚n this relatively new field of hyperelastic materials 鈥 materials that can really stretch 鈥 there鈥檚 been a lot of work, but not in the area of fracture control,鈥 German said. 鈥淔racture control has only been explored in more brittle materials.鈥
What鈥檚 particularly important, Maiorana and German said, is having PDMS as the basis for the flexible membrane, since it is known for its wide variety of uses. The study also integrates other common materials.
鈥淲e do it without using any exotic material,鈥 Maiorana said. 鈥淲e鈥檙e not inventing some new metal or ceramic. We鈥檙e using rubber or modifying normal glass to do these things. We鈥檝e taken this really basic idea and made it functional.鈥
German鈥檚 ongoing research on human skin made him realize that the outermost layer 鈥 known as the stratum corneum - exhibits a network of v-shaped topographical microchannels that appear to be capable of guiding fractures to the skin.
This study began with the idea of recreating this effect in nonbiological materials. Previous attempts to direct microcracks have utilized more solid means, such as copper films around the most sensitive parts of flexible electronics components.
鈥淓ven though this membrane looks and feels exactly like a normal, boring membrane,鈥 he said, 鈥測ou stretch it and you can get cracks to deviate at 45-degree angles away from where it ordinarily would have cracked. I think it鈥檚 pretty cool.鈥
Because of the long fabrication period for the membranes, Maiorana often would spend a week to produce one and then tear it apart in a matter of seconds 鈥 only to start all over again with the next one. He credited the increasing precision of additive manufacturing and its ability to print ever-smaller features for making the production of the membranes possible.
鈥淐hris was designing his own fabrication systems to make these substrates,鈥 German said, 鈥渂ecause he had to 3-D print a mold and then use this clever system to control the depth of these canyons in the substrate. It鈥檚 really technically challenging.鈥
Maiorana added: 鈥淭here is a certain level of art to it. You think there鈥檚 an entire scientific process, and there is, but part of it is that you鈥檝e done this process before and you know what it鈥檚 supposed to look like.鈥
This study, German said, furthers the quest of biomedical engineers to learn from what nature has already perfected.
鈥淚t doesn鈥檛 matter how good an engineer you are 鈥 evolution thought of it first,鈥 he said. 鈥淓volution always wins.鈥
The studyalso included research from Mitchell Erbe, Travis Blank and Zachary Lipsky. It was supported by German鈥檚 National Science Foundation CAREER Award ().