Tamara Flores
Get ready for a future straight out of a spy movie! Smart contact lenses are no longer just a figment of our imagination. In fact, researchers have been hard at work developing these incredible lenses for a variety of mind-blowing uses. From monitoring glucose levels to potentially detecting cancer, and even taking photos with our eyes, the possibilities are endless.
But there’s been one major hurdle in their development: how to power these lenses safely and conveniently. Traditional batteries with metal wires are a no-go, as they pose risks to our delicate eyes. That’s why a team of researchers at Nanyang Technological University Singapore turned to the eye itself for inspiration.
“We had a simple question in mind,” said Lee Seok Woo, the lead author of the study. “Could we recharge contact lens batteries with our tears? We’ve seen self-charging batteries powered by human perspiration in wearable technology, so why not tears?”
The team successfully created a bio-safe battery that’s as thin as the human cornea. Using tears as their guide, they coated the battery with an enzyme called glucose oxidase, which reacts with the sodium and chloride ions found in tears. This reaction, known as reduction, generates electricity. The battery also contains water, acting as “circuitry” for the electricity.
“It relies on just glucose and water to generate electricity,” explained Woo. “Both of these components are safe for humans and have less environmental impact when disposed of compared to conventional batteries.”
To put their creation to the test, the researchers placed the battery in a simulated eye using saline solution to mimic tears. And guess what? It worked! The battery produced a current of 45 microamperes and a maximum power of 201 microwatts. It could even discharge power up to 200 times, which is only around 100 times less than a typical lithium-ion battery.
With a battery that’s already capable of powering a smart contact lens, the team is now focused on improving the amount of electrical current it can produce. The future of smart contact lenses is looking brighter than ever!
So, keep your eyes peeled for more exciting developments in the world of smart contact lenses.
The study is published in the journal Nano Energy.
