Sci-fi themed movies and TV series have often hypothesized the use of smart contact lenses. An invention that today, thanks to the work of a group of scientists from Singapore's Nanyang Technological University, seems to be one step closer to reality.
However, the use of the futuristic product should not only be thought of in the field of espionage, but above all in the field of medicine, since studies on lenses capable of monitoring glucose levels and diagnosing cancer are already at an advanced stage. , but also to photograph with the eyes.
The biggest obstacle to realizing these marvels of microtechnology lies in power, as existing batteries depend on alloys containing metals that would be unsafe to place in such a delicate part of the human body as the eye.
But that's exactly where the work of the Singaporean team fits in, having designed a power generator just half a millimeter thick and capable of powering the hypothetical smart lens thanks to a special feature. And it can be refilled with tears.
The micro-battery coating contains an enzyme known as glucose oxidase, capable of generating electricity by using a small amount of water as a circuit to cause the chemical reaction with sodium and chloride ions present in ocular secretions.
The battery has so far been tested exclusively on a laboratory replica of the human eye, using a simple saline contact lens solution instead of tears. The result showed that a current of 45 microamps and a maximum power of 201 microwatts could be produced.
The next step is to aim for a better quality of the current generated and to make the power supply even more efficient and long-lasting, since it was possible to recharge the prototype approximately 200 times in total, compared to 300 for a normal battery with lithium.