Testing of yeast cells damage using hydrogen peroxide spiking and Pd-NPs-based electrodes and impact of oxidoreductase presence on electrochemical read-out

Herein, a rapid electrochemical approach for testing of yeast cells damage using hydrogen peroxide spiking and Pd-NPs-based electrodes was proposed. The approach is based on the analyzing of electrochemical interactions between the droplets of yeast suspension spiked with hydrogen peroxide solutions (H2O2) and the surface of screen printed electrode modified by palladium nanoparticles (Pd-NPs). For the intact cells the characteristic anodic electrochemical signal recorded at 0.28 – 0.3 V remains at a constant level due to self-regulation processes regardless the spiked amount of hydrogen peroxide. In contrast, the increase of the anodic current corresponding to the added H2O2 concentration reflects the damage of yeast cells. Significantly, by introduction of peroxide-sensitive oxidoreductase in the design of Pd-NPs, which led to the formation of hybrid oxidoreductase-Pd-NPs electrodes, it was possible to modify the electrochemical read-out of the proposed approach.