Real-time Analysis of Electrolytes in Sweat Through a Wearable Sensing Platform

Abstract

The field of biochemical sensing is evolving from the use of bulky apparatuses to the development of miniaturized systems allowing personal sensing and point of care analysis. We report a wearable platform capable of measuring the concentration of multiple electrolytes in sweat (Na+, K+, Cl−). The platform accesses sweat emerging through the skin, drawing it across solid-state ion-selective electrodes by capillary action. The electrolyte composition is monitored in real time by potentiometry. The sensor data is digitised and transmitted via Bluetooth to a mobile phone or laptop. The platform has been employed in on-body trials during controlled exercise.

Wearable Osmotic-Capillary Patch for Prolonged Sweat Harvesting and Sensing

“…Osmotic forces (from ion pumps in the sweat glands) drive the sweat through narrow capillary dermal ducts to the surface of the skin to regulate the internal body temperature. , Targeting sweat as a potential alternative biofluid for non-invasive sampling and sensing of analytes (electrolytes, metal ions, metabolites, proteins, and exogeneous chemicals) has received significant and growing attention recently since it contains solutes that otherwise need to be extracted invasively from blood. − Wearable sweat-based sensors represent a growing field of research and an emerging class of technology. They offer the promise of real-time health monitoring to provide useful information for personalized health care. , …”

“…They offer the promise of real-time health monitoring to provide useful information for personalized health care. 4,5 One of the biggest challenges for sweat analysis is sampling sweat samples of sufficient volume for assays. Most existing devices are either invasive in nature 6,7 or are only functional under "active sweating"; i.e., sweat released due to physical exertion prior to testing.…”

Potentiometric ion-selective sensors based on UV-ozone irradiated laser-induced graphene electrode

“…In recent years, electrochemical sensors have emerged as a popular device for real-time analysis and non-invasive monitoring of human body fluids such as urine, blood, sweat, tears, saliva and interstitial fluid [1][2][3][4]. It is important to detect and quantify the concentration of biomarkers such as metabolites, proteins, antibodies, electrolytes, ions and hormones which can provide crucial information about health and physical status of a person [2,[4][5][6][7][8]. Analysis of sweat has drawn great attention as it contains chemical and biological markers that are responsible for many diseases and physiological disorders such as dehydration, cystic fibrosis, stress disorders, bone mineral loss, hyponatremia, osteoporosis and drug abuse [4,[8][9][10][11][12][13][14][15].…”