TECHNOLOGY SO TRUMPETS

SOMEDAY soon, perhaps within a year, you'll be able to slap a soft, stretchy patch on your arm that tells you if  you're dehydrated. 

Or that you're electrolytes are dangerously out of balance. Or even that you've diabetes.

Fitness trackers such as  Fitbit and Apple Watch already track step counts, heart rate and sleep rhythms. But they tend to be rigid and bulky, and mostly gather mechanical metrics rather than assess a person's underlying biology.

Now there is a new generation of devices that aim to analyze sweat for many chemicals at once, producing a real-time snapshot  of the wearer's health or fitness.

Those devices also fit intimately against the skin and are comfortable for anyone, from premature babies to the elderly. One version is already being advertised by  Gatorade.

The latest advances in this technology, described in the Journal Science Advances, provides real-time  information on the wearer's pH, sweat rate and levels of chloride, glucose and and lactate - high levels which could signal cystic fibrosis, diabetes or lack of oxygen.

''It fits into broader trend that you're seeing in medicine, which is personalized, tailored approaches to treatment and delivery of care,'' said John Rogers, a biomedical engineer at North Western University in Illinois and the key architect of the device.

Technology like this has been anticipated for years, but recently the field has accelerated rapidly. Some similar devices are in development are soft. Some are electric sensors to read chemicals. Others rely on on colormetrics, in which the intensity of the color in the readout matches the concentration of the chemical being monitored.

The new device delivers all of that in a battery-free and wireless form.

''This looks like the first version in which they integrated all of it in one device,'' said Martin Kaltenbrunner, an engineering professor at Johannes Kepler University Linz in Austria, who was not involved in the research.

''The level of technology that is in this paper is very, very advanced.''

The new device has  minuscule holes at its base into which sweat naturally flows. from there, a complex network of valves and microchannels, each roughly the width of human hair route the sweat into tiny reservoirs.

Each reservoir contains a sensor that reacts with the chemical in the sweat, such as glucose or lactate.

''That's basically it,'' Dr. Rogers said.

''There's nothing that penetrates the skin, and there's no power supply that's driving flow.''

The honor and serving of the latest Inventions and Technology, continues to part 2. The World students Society thanks author and researcher Aporva Mandavilli.