The world's first 1cm chip to measure blood sugar levels

Geneva: Scientists have developed the world's first biosensor chip that is implanted under the skin to measure not just pH and temperature but also blood cholesterol or sugar levels, as well as drugs.

The chip is only a centimetre long, is powered by a patch on the surface of the skin and it communicates with a user's mobile phone.

The biosensor chip developed at EPFL in Switzerland is capable of simultaneously monitoring the concentration of a number of molecules, such as glucose and cholesterol and certain drugs.

The future of medicine lies in ever greater precision, not only when it comes to diagnosis but also drug dosage, researchers said.

The latest development is the biosensor chip, created by researchers in the Integrated Systems Laboratory working together with the Radio Frequency Integrated Circuit Group.

"This is the world's first chip capable of measuring not just pH and temperature, but also metabolism-related molecules like glucose, lactate and cholesterol, as well as drugs," said Sandro Carrara.

A group of electrochemical sensors works with or without enzymes, which means the device can react to a wide range of compounds, and it can do so for several days or even weeks.

This one-centimetre square device contains three main components: a circuit with six sensors, a control unit that analyses incoming signals, and a radio transmission module.

It also has an induction coil that draws power from an external battery attached to the skin by a patch.

"A simple plaster holds together the battery, the coil and a Bluetooth module used to send the results immediately to a mobile phone," said Carrara.

The chip was successfully tested in vivo on mice at the Institute for Research in Biomedicine (IRB), where researchers were able to constantly monitor glucose and paracetamol levels without a wire tracker getting in the way of the animals' daily activities.

The results were extremely promising, which means that clinical tests on humans could take place in three to five years - especially since the procedure is only minimally invasive, with the chip being implanted just under the epidermis, researchers said.

"Knowing the precise and real-time effect of drugs on the metabolism is one of the keys to the type of personalised, precision medicine that we are striving for," said Carrara.