Researchers from the University of Houston have developed a new way to check glucose levels: through contact lenses. This would be the first time that a non-invasive method was used to check glucose levels in body fluids. The technology used to detect glucose via optical means is known as surface-enhanced Raman scattering spectroscopy. Shih and his team developed a way to enhance it further through what is called nanoplasmonics.
In Raman scattering, how light interacts with a material can determine properties of the molecules that make up the material. Shih took advantage of this technique’s ability to detect tiny molecular samples by building a device that would intensify the Raman signal. The device is made out of several layers of gold nanowires stacked on top of a gold film. The device is then created through nanotransfer printing. The narrow gaps created within the resulting nanostructure now further enhance the Raman scattering technique.
With wearable electronics in mind, Shih’s team created the material to be flexible. This was done by lifting the hard substrate off the layered nanoarray and then printing it onto a soft contact. This made it possible to attach the material in a contact lens.
A glucose-sensing contact lens is not exactly one-of-a-kind. Google already has a patent filed for a cutting-edge contact lens that can also detect glucose levels in tears and many more. Shih’s team insists that their technology can also be used in other applications besides glucose level monitoring.
“It’s one of the grand challenges to be solved,” Shih said, referring to other potential applications of their project. He said that creating a contact lens out of their material is one good way that the technology actually works.
Shih mentions that the correlation between tear glucose and blood glucose is yet to be established. Glucose has been known to be present in tears but if its levels are significant for real diagnostics is still unclear.
More information can be found at: University of Houston.