For diabetics: Contact lenses that measure sugar levels in tears

Eyes are known as windows to the soul, and they’re also the doors to a potential breakthrough for diabetics. GoogleX Labs, the inventors of Google Glass and Google’s self-driving cars, is developing a “smart” contact lens that could replace the painful and repetitive pinpricks diabetics have to endure – sometimes hourly – throughout the day when monitoring their blood glucose levels. Outfitted with a miniscule wireless chip and sensor, the device will be capable of accurately and consistently measuring the levels of glucose in the tears of diabetics – possibly as frequently as once per second.

According to a joint posting in a blog by product co-developers, Brian Otis and Babak Parviz, “Many people…say managing their diabetes is like having a part-time job. It’s disruptive, and it’s painful. And, as a result, many people with diabetes check their blood glucose less often than they should.”

Diabetes is a sprawling health problem that has reached epidemic proportions. According to the International Diabetes Federation, more than one in 20 people currently have this chronic condition – which equates to approximately 347 million people worldwide – and that number is expected to leap to approximately one in 10 by 2035.

When an individual has diabetes, their body is incapable of regulating its own blood sugar, also known as glucose, because it has a deficiency of the sugar-regulating hormone, insulin. Mundane activities such as eating, exercising or even sweating can cause extreme glucose fluctuations. People stricken with this affliction need to check their levels of glucose numerous times per day with a painful pinprick to the fingers to draw droplets of blood, which are then placed on a testing implement. Many diabetics take the glucose-stabilizing hormone insulin, which is often self-administered with a hypodermic needle. Blood sugar levels can spike or plunge to extremes, resulting in the risk of gangrene, kidney failure, blindness, amputations, coma or even premature death if recurring glucose testing is neglected.

GoogleX’s contact lens device, which is painless and easy to place in the eye, could be a complete game-changer in a diabetic’s quality of life. Rigged with miniaturized processing chips (think: the size of glitter) and a glucose sensor, it also contains an antenna that’s thinner than a human hair. At times, Otis – an expert in miniaturized systems – and his team had to create new chip-manufacturing tools so that all of the lens’ components could be built small enough. How does it work? Throughout the day, the eye generates tears to keep itself moist and healthy. The tears seep into a pore in the contact lens, permitting the sensor to decipher their glucose content. Next, the antenna can relay a signal to a smartphone or other device to inform the lens wearer of their glucose reading.

In the 1930s, French researchers deduced that tears are infused with measurable levels of glucose, but it has taken decades to discover a means of exploiting that knowledge to create a test that is non-invasive. At the University of Michigan in Nov. 2011, a team displayed a sensor which tested tears – and even then, they were one of a variety of teams experimenting with the idea. Microsoft Research, which was then collaborating with Parviz – a University of Washington professor at the time – disclosed a prototype of the glucose-measuring contact lens in 2011.

According to Otis and Parviz, “We’re also investigating the potential for this to serve as an early warning for the wearer, so we’re exploring integrating tiny LED [light emitting diode] lights that could light up to indicate that glucose levels have crossed above or below certain thresholds.”

These lights would only be visible to the wearer, and would change color to specify whether glucose levels are too high, too low, or just right. The only drawback challenging Otis and Parviz is the fact that LEDs contain the toxic metal, arsenic.

High-tech bionic implants can currently be used to continuously measure blood sugar, but such implants are expensive, invasive, and often difficult to remove. “There are a bunch of sensors out now, which go under the skin and connect with insulin devices such as insulin pumps,” stated Robert Rapaport, M.D., Director of Pediatric Endocrinology and Diabetes at the Mount Sinai Kravis Children’s Hospital, in an interview with Healthline. “Any advance on this would be quite welcomed.”

Google is currently involved in discussions with the U.S. Food and Drug Administration about selling the lens as a medical device, and is seeking business partners within the medical community to bring a smart contact lens and associated apps to market.

“We’ve always said that we’d seek out projects that seem a bit speculative or strange,” attest Otis and Parviz. “And at a time when the International Diabetes Federation is declaring that the world is ‘losing the battle’ against diabetes, we thought this project was worth a shot.”