Caltech’s Wei Gao has developed a wearable sensor that monitors metabolites and nutrients in blood by analyzing sweat. Previously developed, less sensitive, sweat sensors mostly target electrolytes, glucose, and lactate.
Gao develops devices based on microfluidics, which minimize the influence of sweat evaporation and skin contamination on sensing accuracy. Previous microfluidic-based wearable sensors were mostly fabricated with a lithography-evaporation process, requiring complicated and expensive fabrication processes. Gao uses graphene.
In a study, the sensor was used to measure respiratory rate, heart rate, and levels of uric acid and tyrosine. Tyrosine can indicate metabolic disorders, liver disease, eating disorders, and neuropsychiatric conditions. Elevated Uric acid is associated with gout.
Gao believes that the high sensitivity of the sensors, and the ease with which they can be manufactured, could enable them to be used at home to monitor gout, diabetes, and cardiovascular diseases.