An enzyme logic bioprotonic transducer

Translating ionic currents into measureable electronic signals is essential for the integration of bioelectronic devices with biological systems. We demonstrate the use of a Pd/PdHx electrode as a bioprotonic transducer that connects H+ currents in solution into an electronic signal. This transducer exploits the reversible formation of PdHx in solution according to PdH <-> Pd + H+ + e(-), and the dependence of this formation on solution pH and applied potential. We integrate the protonic transducer with glucose dehydrogenase as an enzymatic AND gate for glucose and NAD(+). PdHx formation and associated electronic current monitors the output drop in pH, thus transducing a biological function into a measurable electronic output. C 2014 Author(s).