The effect of repeated activation on screen-printed carbon electrode cards

Screen-printed carbon electrode cards have been recognized as an inexpensive and disposable sensing option with wide application. Despite their disposability, laboratories with high sample throughput may desire repeated use from each card. This study examined the ability of a commercial brand of cards to be reused using cyclic voltammetry (CV) and the reversible redox couple, hexaammine ruthenium. Activation, which improves electrode performance, was shown to affect the shape of the CV curves, the transfer coefficient, and the real electro-active surface area. Repeated activation has a compounding effect on these parameters, which provide insight to the condition and kinetics of the electrode surface. It was determined that screen-printed carbon electrode cards should not be reused with protocols that require electrochemical activation of the working electrode.