The effect of the evaporation rate on electrochemical measurements with paper-based analytical devices and its minimisation by enclosure with adhesive tape.

In this work, the effect of liquid evaporation on electrochemical measurements with electrochemical paper-based devices (ePADs) is studied. The time evolution of cyclic voltammograms of ferricyanide is used to study the effect of liquid evaporation under different conditions of relative humidity and air currents. Moreover, the enclosure of ePAD channels with adhesive tape is evaluated in terms of minimising the evaporation, as well as increasing the sensitivity in the electrochemical determination of horseradish peroxidase in long-term assays. Unlabelled Image • Electrochemical measurements made using uncovered paper-based analytical devices depend on the evaporation rate. • Enclosure of the paper channels with adhesive tape is effective in minimising this dependence. • Enclosure of the channels can improve the results of long-term assays with electrochemical paper-based analytical devices. [ABSTRACT FROM AUTHOR]