Aerobic exercise is an important component of a healthy lifestyle, but performing it too vigorously can lead to a metabolic imbalance accompanied by considerable pain. The primary concern is a build up of lactate that occurs when the cardiopulmonary system cannot supply enough oxygen to the muscles being exercised. Athletes who want to workout at their peak without redlining their bodies have the option of taking blood samples to test for lactate, but that is neither practical nor affordable for most.
Now researchers at University of California San Diego have developed a skin sensor, based around a temporary-transfer tattoo, that is able to accurately detect lactate in sweat on the skin below it. The device, created by using screen printing methods, provides real-time output of lactate and can warn the wearer when it’s time to take it easy and get some rest. The device was tested on ten volunteer athletes and results showed that the technology can rival blood testing for lactate.
More about the sensor from the article in Analytical Chemistry:
The new epidermal lactate biosensor, displayed in Figure 1, consists of a mediated lactate oxidase (LOx) working electrode, prepared by functionalizing the surface of the printed tattoo electrode with tetrathiafulvalene (TTF) and multiwalled carbon nanotubes (CNT), followed by tethering the LOx enzyme, and a biocompatible chitosan overlayer. The latter prevents the efflux of the biochemical backbone from the reagent layer onto the underlying epidermis.
Article in Analytical Chemistry: Electrochemical Tattoo Biosensors for Real-Time Noninvasive Lactate Monitoring in Human Perspiration