Making a revolutionary biosensor takes blood, sweat and tears. And saliva, naturally.

The researchers examined the potential of these and other biofluids to test human health with tiny, portable sensors for the journal Nature Biotechnology.

In the Nature article, researchers continuously monitor the health with wearable devices. These provide data over time so doctors can track health trends instead of relying on the snapshot that a single blood test provides.

After examining the use of saliva, tears and interstitial fluid, the authors concluded in the Nature article that sweat holds the most promise for noninvasive testing because it provides similar information as blood and its secretion rate can be controlled and measured.

In his Novel Device the lab have been creating new sensors on a wearable patch the size of a Band-Aid that stimulates sweat even when a patient is cool and resting. The sensor measures specific analytes over time that doctors can use to determine how the patient is responding to a drug treatment.

The sensors can be tailored to measure anything from drugs to hormones to dehydration, the senior author said.

Last year the lab created the world's first continuous-monitoring sensor that can record the same health information in sweat that doctors for generations have examined in blood. The milestone is remarkable because the continuous sensor allows doctors to track health over time to see whether a patient is getting better or worse. And they can do so in a noninvasive way with a tiny patch applied to the skin that stimulates sweat for up to 24 hours at a time.

"This is the Holy Grail. For the first time, we can show here's the blood data; here's the sweat data - and they work beautifully together," the senior author said.

The authors published their latest experimental findings in December in the journal Lab on a Chip. The study tracked how test subjects metabolized ethanol. The study concluded that sweat provided virtually the same information as blood to measure a drug's presence in the body.

https://www.uc.edu/news/articles/2019/03/n2074289.html

https://www.nature.com/articles/s41587-019-0040-3

https://pubs.rsc.org/en/Content/ArticleLanding/2018/LC/C8LC01082J#!divAbstract