Potentiometric titration

Catalysis

Voltage

Engineering

Capacitance

Electrochemistry

Materials science

Chromatography

Potentiometric sensor

Embedded system

Ion selective electrode

Computer science

Electrochemical gas sensor

Physical chemistry

Transducer

Transistor

Nanotechnology

Organic chemistry

Solid-state

Environmental chemistry

Wearable computer

Analytical Chemistry (journal)

Field-effect transistor

Chemistry

Selectivity

Electrode

Optoelectronics

ISFET

Electrical engineering

Electrochemistry Communications

There is considerable interest in wearable potentiometric ion sensors that can provide information about the quality of a person's health by monitoring ion concentration levels in biofluids. Significant progress has been achieved, particularly in device integration. However, the crucial interfacial water layer and the use of transducer materials remain challenging. Herein we report a paper-based, flexible, all-solid-state, ion-selective electrode (ISE) for the real-time analysis of sweat. The super-hydrophobic paper matrix was modified with a fluorinated alkyl silane to reduce the water-layer effect. We used a high-quality graphene suspension with high conductivity and capacitance as an ion-to-electron transducer, which further stabilized the potential. The integrated solid ISE has four channels that can detect K+, Na+, Cl− and pH simultaneously. This wearable potentiometric sensor has reliable accuracy, good potential stability and low detection limits, and could be used in healthcare and clinical analysis.

A multichannel electrochemical all-solid-state wearable potentiometric sensor for real-time sweat ion monitoring