Testing Diabetes Through the Eyes

A recent publication of the 2022 National Diabetes Statistics Report by the Centers for Disease Control and Prevention (CDC) estimated that more than 130 million people have diabetes or prediabetes (“CDC 2022”). According to John Elfein, a Statista's research expert for topics concerning health, diseases, and medical professionals in the United States and worldwide, the World Health Organization had estimated that by 2045, the number of diabetics around the world would be around 783 million. As society advances and with the introduction of fast foods and sugary drinks, people are more than likely now to develop diabetes and serious health issues. People with diabetes may experience serious health issues that result when their blood sugar is too low or too high. According to Mayo Clinic, when blood sugar level is too high, one may be at risk for life-threatening dehydration and a diabetic coma. However, one’s blood sugar level cannot be too low because bodily functions will fail to continue properly, and they may experience difficulty walking and even suffer from seizures (“Low Blood Sugar (Hypoglycemia)”). To prevent these health risks, researchers at Stanford University and South Korea’s Pohang University of Science and Technology (POSTECH) developed a contact lens in 2020 that accurately and continually monitors the

wearer’s blood sugar. The contact lens was created using chip technology, which tracks the user's blood sugar levels through the blood vessels behind the eyelids and sends an alert in the event of a medical emergency (“Smart Contact Lenses”). In 2014, Alphabet, a Google subsidiary company, announced that they were in the process of developing similar technology; however, they faced many difficulties in receiving accurate blood sugar data through the wearer’s tears and consequently terminated the project. William McCleary, a medical journalist in HealthTech Insider, explains that issues such as sensor corrosion, instability of the tear enzyme, sluggish absorption of tears into lenses, and the fact that the human eye does not generate enough tears to support continuous monitoring left Alphabet with no choice but to end this project. Despite these challenges, Stanford and POSTECH researchers were able to solve some of the problems that previous researchers had encountered by using a porous hydrogel to better absorb tear fluid. The porosity of the hydrogel has been precisely adjusted to blend in with the delicate film of tears covering the eye. If the hydrogel is too porous, the lens's integrity might be jeopardized. The lens must be sufficiently permeable in order to absorb enough tears to obtain a measurement (McCleary). Moreover, non-corrosive gold and platinum nanoparticle catalysts that have been stabilized over time using hyaluronic acid were studied. A chemical reaction occurs when a tear interacts with the hydrogel, producing electricity that is detected by circuits in the lens. The intensity of the electrical current reveals the amount of glucose in the tear fluid and, consequently, the amount of glucose in the wearer's blood (McCleary). These measures are wirelessly transmitted to a mobile device where an app may be used to see them.

The wearable blood sugar monitoring device with smart contacts is not the first of its kind. For example, there are sensors that may be applied directly to or implanted in the skin. Yet, it has been difficult for any of them to provide reliable findings over the extended periods of time that wearable technology demands. According to Andrew Myers, an award-winning freelance science writer, smart contact lenses are the first glucose monitoring gadget to create a direct association between tears and blood glucose concentrations independently without the help of another medical instrument, such as a glucometer. Not only are smart contact lenses more accurate in receiving and sending glucose information, but it is also more convenient for the wearer to wear the lens and continue with their daily life. The use of these smart contact lenses allows people to be more aware of their own glucose levels and may help to prevent many serious health risks.

References

“CDC 2022 National Diabetes Statistics Report.” Centers for Disease Control and Prevention. 26 Jan.2022. nationaldppcsc.cdc.gov/s/article/CDC-2022-National-Diabetes-Statistics-Report#:~:text=The%20Centers%20for%20Disease%20Control,prediabetes%20in%20the%20United%20States. Accessed 23 Mar. 2023.

“Diabetic Coma.” Mayo Clinic. 11 Aug. 2022. www.mayoclinic.org/diseases-conditions/diabetic-coma/symptoms-causes/syc-20371475#:~:text=When%20blood%20sugar%20is%20very,dehydration%20and%20a%20diabetic%20coma. Accessed 23 Mar. 2023.

Elflein, John. “Diabetes - Statistics & Facts.” Statista. 6 Jan. 2022. www.statista.com/topics/1723/diabetes/#topicOverview. Accessed 23 Mar. 2023.

“Low Blood Sugar (Hypoglycemia).” Centers for Disease Control and Prevention. 30 Dec. 2022. www.cdc.gov/diabetes/basics/low-blood-sugar.html. Accessed 23 Mar. 2023.

McCleary, William. “A New Smart Contact Lens Measures Glucose Levels From Tears.” HealthTech Insider. 12 Aug. 2022. healthtechinsider.com/2022/08/12/a-new-smart-contact-lens-measures-glucose-levels-from-tears/. Accessed 23 Mar. 2023.

Myers, Andrew.”Smart contact lens monitors blood sugar.” Stanford University. cheme.stanford.edu/smart-contact-lens-monitors-blood-sugar Accessed 23. Mar. 2023.

“Smart Contact Lenses Successfully Detect Glucose Levels.” Diabetes.co.uk. 1 May. 2020. www.diabetes.co.uk/news/2020/may/smart-contact-lenses-successfully-detect-glucose-levels.html. Accessed 23 Mar. 2023.