Fashionable fabric becomes a top-of-the-range electrode.

A team of scientists in China has created a wearable sweat monitor out of silk that measures a suite of health biomarkers in real time, including levels of glucose, lactate and potassium.

It’s a leap in materials science that promises new ways of tracking endurance and dehydration in exercise, as well as diseases such as diabetes and kidney failure.

The research, led by Yingying Zhang from the Department of Chemistry at Tsinghua University in Beijing, took its inspiration from a small worm that has been punching above its weight for millennia.

The humble silkworm weaves a single, strong and uniform thread of silk up to 1.5 kilometres long in the process of building its cocoon.

That epic example of personal housing has fed the Chinese silk industry for over 5000 years and also, the researchers write, “[endows] silk fabric with good uniformity and high mechanical strength”.

Silk is famed for its comfort and breathability too, but none of the above a sweat sensor make. Which is where Zhang’s team availed themselves of some very deft new tech.

They heated silk up to 900 degrees Celsius, a natural process that induces a profound chemical change that “carbonises” the fibre.

Imbued with this new carbon structure, silk goes from one of the world’s most desirable fabrics to a top-of-the-range electrode, capable of measuring things in sweat that induce an electric current.

Using a laser device to construct six individual sensors in a patch of the material, Zhang’s team came up with a biscuit-sized swatch of fabric that could measure glucose, lactate, sodium, potassium, ascorbic acid and uric acid.

Read the full story in Cosmos magazine here