A skin patch that measure how stress you are by your sweat has been developed by scientists.
The patch will worn in real time so if someone is getting stressed so they can take steps to avoid it.
If stress is not brought under control it can cause serious illnesses, such as high blood pressure, heart disease, asthma, stroke, diabetes and some types of cancer.
Current it takes days to measure cortisol levels after blood samples are sent off to labs but by the time the results come back and a doctor prescribed treatment, levels may be completely different.
So scientists at Stanford University in California created a stretchy patch that, applied directly to the skin, soaks up sweat and assesses how much cortisol a person is producing.
Wearable health monitoring devices are a growing area of research because not only does it provide real time results but allows patients to be monitored at home.
Lead author post-doctoral scholar Dr Onur Parlak: “We are particularly interested in sweat sensing, because it offers noninvasive and continuous monitoring of various biomarkers for a range of physiological conditions.
“This offers a novel approach for the early detection of various diseases and evaluation of sports performance.
“The resulting wearable sensor was used for measuring cortisol concentration in a real human sweat sample collected during exercise.
“Considering that traditional blood analysis is often used for cortisol sensing, the wearable device provides many advantages including noninvasiveness, ease of operation, and user comfort.”
Dr Parlak added if the prototype version of the wearable device becomes a reality, it could allow people with an imbalance in their adrenal or pituitary gland to monitor their own levels at home.
The real time monitor could also reveal the emotional state of young – even non-verbal – children, who might not otherwise be able to communicate that they feel stress.
Cortisol presents a special challenge to biosensors because these sensors detect a molecule’s positive or negative charge – and cortisol has no charge.
So the researchers built the stretchy, rectangular sensor around a membrane that specifically binds only to cortisol.
Stuck to the skin, it sucks in sweat passively through holes in the bottom of the patch.
The sweat pools in a reservoir, which is topped by the cortisol-sensitive membrane.
Charged ions like sodium or potassium, also found in sweat, pass through the membrane unless they are blocked by cortisol.
It’s those backed up charged ions the sensor detects, not the cortisol itself.
On top of all this is a waterproof layer that protects the patch from contamination.
All a patient needs to see cortisol levels is to sweat enough to glisten such as a 20 minute run, apply the patch and connect it to a device for analysis, which gives results in seconds.
In the future, the researchers hope the sensor could be part of a fully integrated system.
And the aim is to test the cortisol sensor on saliva, which would avoid patients needing to sweat.
The study was published in the journal Science Advances.
