A graphene oxide pH sensor for wound monitoring

This article describes the fabrication and characterization of a pH sensor for monitoring the wound status. The pH sensitive layer consists of a graphene oxide (GO) layer obtained by drop-casting 5 μl of GO dispersion onto the working electrode of a screen-printed substrate. Sensitivity was 31.8 mV/pH with an accuracy of 0.3 unit of pH. Open-circuit potentiometry was carried out to measure pH in an exudate sample. The GO pH sensor proved to be reliable as the comparison with results obtained from a standard glass electrode pH-meter showed negligible differences (< 0.09 pH units in the worst case) for measurements performed over a period of 4 days.