Many people with diabetes need to prick their fingers and drip blood eight times a day to monitor their blood sugar levels, an uncomfortable and cumbersome task. Over the course of a person's lifetime, this can add up to tens of thousands of finger pricks.
Now, South Korean researchers may have a way to measure blood sugar without finger pokes: the scientists have developed a glucose monitor embedded in a soft contact lens that measures glucose levels in tears and wirelessly transmits that information to a handheld device ...... You don't even have to cry.
The device has so far been tested only on live rabbits, with no signs of discomfort. But the researchers who invented the device predict that the sugar-sensing contact lenses could be commercially available in less than five years. The device would be placed in one eye and not used to correct vision like traditional contact lenses. [The device is described in an article published today (Jan. 24) in the journal Science Advances.
More than 30 million Americans, or 9.4 percent of the U.S. population, have type 2 diabetes, and another 80 million have prediabetes, according to the disease's control system. million people have prediabetes, which, if left untreated, typically leads to type 2 diabetes within five years, according to a 2017 report from the Centers for Disease Control and Prevention. Diabetes is also a health issue in South Korea, where the prevalence of diabetes rose from 5.6 percent in 2006 to 8 percent in 2013, according to the Korean National Health Insurance Service.
Diabetes is a condition in which the body periodically experiences higher-than-normal blood sugar levels. The cause may be that the pancreas does not produce enough insulin to help metabolize glucose (known as type 1 diabetes) or, more commonly, that the body does not use insulin correctly (known as type 2 diabetes).
In both cases, many (but not all) people with diabetes need to monitor their blood sugar levels today throughout the course of their disease. Prolonged elevated blood sugar can damage blood vessels and increase the risk of heart disease, stroke, kidney disease, vision problems, and nerve problems.
A glucose-sensing lensPrevious attempts to embed glucose monitors in contact lenses have been fraught with difficulty. The electronics were too brittle and the lenses too hard, resulting in a fragile device that was both uncomfortable and prone to breakage, said Jang Young Park, a professor of engineering at the National Institute of Science and Technology in Ulsan, South Korea. Elements in these early devices also obscured vision and could damage the eyes, according to the paper, "KdSPE" "KdSPS," but recent advances in materials science and nanotechnology have allowed Park's team to design flexible or stretchable structures and circuits, including an LED display embedded in a lens.
The resulting product measures glucose levels in natural tears in real time and communicates that data through an LED display that can emit a non-invasive light if glucose levels are too high. Alternatively, a tiny antenna is included in the lens and the information can be transmitted wirelessly.
"The key difference is that the soft lens has retractable electronics and a display," Parker told Live ScienceThe soft contact lenses are retractable and can be flipped. As a result, the LEDs can fire into the wearer's eyes or in the opposite direction, depending on the wearer's choice.
Glucose monitoring is optional for some people who don't need insulin injections. But everyone who uses insulin to regulate their condition must have a glucose test, even if it's just to calibrate the glucose monitor. That includes 1.25 million people with type 1 diabetes and another six with diabetes. Regarding type 2 diabetes, according to the American Diabetes Association (ADA),
a blood sample on a finger stick is the gold standard for accurate blood sugar measurement. Techniques for measuring glucose in tears have been available for years, but are often not accurate enough for a variety of factors; for example, glucose levels may be lower when your eyes are wetter from allergies or crying.
"Glucose levels in tears do correlate with blood glucose levels, [so] there's still a lot of research to be done to clarify the correlation between tear glucose levels and blood glucose levels, as well as how closely tear glucose levels correlate with blood glucose levels," Matt Peterson, managing director of ADA Medical Information, told Live Science. "However,
" ", the researchers who invented the new lens-based device said that monitoring glucose through tears could be a convenient alternative to blood measurements because it is done continuously in real time to compensate for sampling inconsistencies.
Peterson noted that while there are challenges with tear testing, the potential for eliminating finger sticks may appeal to people with diabetes.
The researchers hope that their technology for embedding sensors in soft contact lenses can also be applied to other areas, such as smart devices for drug delivery, augmented reality, and even monitoring biomarkers via smartphones.
Follow Christopher Wanjek @Wanjek for daily tweets on health and science with a touch of humor.Wanjek is the author of Food at Work and Bad Medicine. His column, "Bad Medicine," appears regularly in Life Science