A blood glucose monitoring contact lens could soon allow doctors and patients to track glucose levels and other vital health indicators without invasive tests. Scientists say the bio sensing lenses, based on technology that led to the development of smartphones with more vivid displays, could also potentially be used to track drug use or serve as an early detection system for cancer and other serious medical conditions.<\/p>\n
Researchers presented their work at the 253rd National Meeting and Exposition of the American Chemical Society, the world’s largest scientific society, featuring more than 14,000 presentations on a wide range of science topics.<\/p>\n
“These biosensors probably won’t put blood labs out of business,” said Gregory S. Herman, Ph.D. “But I think that we can do a lot of diagnostics using information that can be extracted from tear drops in the eye.”<\/p>\n
Herman first conceived of bio sensing while working in industry, where he and two colleagues invented a compound composed of indium gallium zinc oxide. This semiconductor revolutionized electronics, offering consumers higher resolution displays on televisions, smartphones, and tablets while saving power and improving touch screen sensitivity.<\/p>\n
After moving to Oregon State University in 2009, Herman began investigating the technology’s biomedical applications \u2014 in particular, developing a blood glucose monitoring contact lens to help people with diabetes continuously track their glucose levels more efficiently.<\/p>\n
Continuous glucose monitoring, rather than the traditional prick and test approach, helps reduce the risk of diabetes related health problems. However, most continuous glucose monitoring systems require inserting electrodes under the skin, which can be painful and cause skin irritation or infections.<\/p>\n
A blood glucose monitoring contact lens could eliminate many of these problems. Users can easily replace the lenses on a daily basis, and unlike skin electrodes, they are invisible \u2014 helping users feel less self conscious about managing their condition.<\/p>\n
To develop the blood glucose monitoring contact lens, Herman and his colleagues first created an inexpensive method to make IGZO electronics. They then fabricated a biosensor containing a transparent sheet of IGZO field effect transistors and glucose oxidase, an enzyme that breaks down glucose. When glucose was added, the enzyme oxidized the blood sugar, shifting the pH level and triggering changes in electrical current through the transistor.<\/p>\n
Because glucose concentrations are much lower in the eye than under the skin, the team created nanostructures within the biosensor capable of detecting glucose concentrations far lower than those found in tears \u2014 making the blood glucose monitoring contact lens sensitive enough for real world use.<\/p>\n
In theory, more than 2,500 biosensors \u2014 each measuring a different bodily function \u2014 could be embedded in a 1 millimeter square patch of an IGZO contact lens. Once fully developed, the biosensors could transmit vital health information to smartphones and other Wi-Fi or Bluetooth enabled devices.<\/p>\n
Herman’s team has already used the IGZO system in catheters to measure uric acid, a key indicator of kidney function, and is exploring its potential for early detection of cancer and other serious conditions. However, it could be a year or more before a prototype blood glucose monitoring contact lens is ready for animal testing.<\/p>\n
This kind of innovation in continuous monitoring aligns closely with the broader movement toward personalized medicine and decentralized healthcare delivery. For more on how new treatments move from research into clinical use, our introduction to clinical trials<\/a> explains the full development pathway.<\/p>\n For those managing diabetes and looking to understand more about the condition itself, our article on types of diabetes<\/a> provides a comprehensive overview of causes, diagnosis, and management strategies.<\/p>\n