Smart sweat-detecting skin patch knows when you're dehydrated

Meet the wearable that will keep a check on your water intake
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We've already talked about why hydration monitoring wearables are going to be a big deal and now researchers at Northwestern University have been busy developing a skin patch that can keep tabs on hydration and more.

The discreet patch-like device measures in about 2.5cm in diameter and sticks to the skin either on the forearm or back. From there the electronic sensor, which is made up of four separate compartments is able to measure four biomarkers markers found in sweat - PH, glucose concentration, chloride and lactate.

Read this: What wearables will measure in the future

When the sweat enters the different compartments, it creates a chemical reaction that changes the colour of the sensor. These changes in colour can signify hydration and electrolyte levels. The user can then take a picture of the changes on their smartphone and with the companion app determine what the colours actually mean.

The team of researchers have already run tests with a group of 21 cyclists, with nine of the volunteers taking part in an indoor cycling session where the sensors were compared to lab-based sweat analysing techniques. The other volunteers put the wearable to the test in a race across a desert in Arizona. As well as the patches staying put and not causing any irritation, the data also matched up with the lab measuring techniques.

"Sweat is a rich chemical broth containing a number of important chemical compounds with physiological health information," said Professor John A Rogers, who led the research team at Northwestern University.

"By expanding our previously developed 'epidermal' electronics platform to include a complex network of microfluidic channels and storage reservoirs, we now can perform biochemical analysis of this important bio-fluid."

While fitness is looking likely to be the best fit for the smart skin patches, Rogers also believes it could potentially be used to screen patients for diseases such as cystic fibrosis and diabetes.

Unsurprisingly, the patches are not quite ready to go into production just yet, but it looks like the research team has made some good progress getting them ready for the masses to try out.

Source: Digital Trends

Smart sweat-detecting skin patch knows when you're dehydrated

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Michael Sawh


Michael Sawh has been covering the wearable tech industry since the very first Fitbit landed back in 2011. Previously the resident wearable tech expert at Trusted Reviews, he also marshaled the features section of

He also regularly contributed to T3 magazine when they needed someone to talk about fitness trackers, running watches, headphones, tablets, and phones.

Michael writes for GQ, Wired, Coach Mag, Metro, MSN, BBC Focus, Stuff, TechRadar and has made several appearances on the BBC Travel Show to talk all things tech. 

Michael is a lover of all things sports and fitness-tech related, clocking up over 15 marathons and has put in serious hours in the pool all in the name of testing every fitness wearable going. Expect to see him with a minimum of two wearables at any given time.

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