A recently developed wristband can analyse bodily fluid such as sweat to give an insight into health while a person works out, claimed a study.

The stretchy patch developed at King Abdullah University of Science and Technology (KAUST) could help in tracking health by making it easier to analyse sweat for critical biomarkers.

The study was published in the journal Small.

Human perspiration contains trace amounts of organic molecules that can act as measurable health indicators. Glucose fluctuations, for example, may point to blood sugar problems, while high levels of lactic acid could signal oxygen deficiencies.

To detect these molecules, researchers are developing flexible prototypes that sit on the skin and direct sweat toward special enzyme-coated electrodes.

The specific nature of enzyme-substrate binding enables these sensors to electrically detect very low concentrations of target compounds.

One obstacle with enzyme biosensors, however, is their relatively short lifetimes.

“Even though human skin is quite soft, it can delaminate the enzyme layer right off the biosensor,” said Yongjiu Lei, a researcher.

Lei and his colleagues have now developed a wearable system that can handle the rigours of skin contact and deliver improved biomarker detection.

The device runs on a thin, flat ceramic known as MXene that resembles graphene but contains a mixture of carbon and titanium atoms.

The metallic conductivity and low toxicity of this 2D material make it an ideal platform for enzyme sensors, according to the studies.

When the team placed the biosensor into a wristband worn by volunteers riding stationary bicycles, they saw lactose concentrations in sweat rise and fall in correlation with workout intensities. Changes in glucose levels could also be tracked as accurately in sweat as it is in blood.

“We are working with KAUST and international collaborators under the umbrella of the Sensors Initiative to integrate tiny electrical generators into the patch. This will enable the patch to create its own power for personalised health monitoring,” said Husam Alshareef, who led the project.