Fig. 4: Examples for electrolytes sensing.
From: A review of sampling, energy supply and intelligent monitoring for long-term sweat sensors
a A flexible charge-coupled device can be used to create a sensor capable of measuring the pH of sweat with high sensitivity. Ref. 72, Copyright 2018, Nature Electronics. b A wearable electrochemical device for continuous monitoring of ionized calcium and pH of body fluid. Ref. 73, Copyright 2016, ACS Nano. c Illustration of WPIS based on a bracelet that was modified with the working/indicator electrode (WE) and a reference electrode (RE) to provide a WPIS. Ref. 77, Copyright 2018, Trends in Analytical Chemistry. d An integrated device to monitor the physiological concentration of two cations, ammonium (NH4+) and calcium (Ca2+). Ref. 78, Copyright 2019 Advanced Healthcare Materials.
