Self-Tuning Reaction Conditioning of a Paper-Based Electrochemical Biosensor for Acetaldehyde Detection

We report a self-tuning reaction conditioning strategy for a paper-based electrochemical biosensor for identifying acetaldehyde. In this study, a three-electrode system was integrated onto paper that had already been cut into shape where the working electrode was modified by the incorporation of aldehyde dehydrogenases (ALDHs). A high concentration of acetate buffer embedded inside the electrode allowed ideal conditions where every measurement taken always results in the same optimum pH. The conditioned paper-based electrode demonstrated a rapid response within ∼20–30 s and a similar linear response at lower and higher acetaldehyde concentrations at pH 4 and 8. Because of our novel electrode preparation strategy, each measurement resulted in the same optimal conditions for enzyme activity ensuring precise and sensitive evaluation of acetaldehyde.