A self-powered biosensing electronic-skin for real-time sweat Ca2+ detection and wireless data transmission

A self-powered biosensing electronic-skin (e-skin) for real-time sweat Ca2+ detection and wireless data transmission has been presented. The material system consists of PANI (with NOX5 and NADPH modification), PDMS and Cu (as electrodes). Based on the triboelectrification/enzymatic-reaction coupling effect, the self-powered e-skin can harvest tiny mechanical energy from human motion and directly output biosensing signals. The outputting triboelectric current is significantly dependent on the Ca2+ concentration in sweat. The response is up to 40.15 against 2.2 × 10−1 g l−1 Ca2+. The triboelectric output can be treated not only as the biosensing signal but also as the power supply for driving the whole system, e.g. wirelessly transmitting the biosensing information. This work can provoke a new research direction for developing self-powered smart healthcare system and wearable electronics.