Abstract
The simple and effective approach of “dipping and drying” cotton yarn in a dispersion of poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS) and multi-walled carbon nanotubes (MWCNT) resulted in the development of a highly conductive and flexible cotton fibres. Subsequent polyaniline (PANi) deposition yielded electrodes with significant biocompatible and antibacterial properties that could be fabricated (alongside quasi-reference electrodes) into solid-state wearable pH sensors, which achieve rapid, selective, and Nernstian responses (-61 ± 2 mV pH-1) over a wide pH range (2.0 – 12.0), even in a pH-adjusted artificial sweat matrix. This development represents an important progression towards the realisation of real-time, on-body, wearable sensors.