Electrochemically switchable and tunable luciferase bioluminescence

The biocatalytic activity of electrode-immobilized luciferase followed by bioluminescence emitted from the electrode surface was reversibly tuned and switched by applying electrochemical signals. When a reductive potential (-0.9 V vs. Ag/AgCl) was applied, O₂ was consumed at the electrode resulting in its depletion in a thin film near the electrode surface. This resulted in the inhibition of the immobilized luciferase which needs O₂ for the biocatalytic reaction. Releasing the potential resulted in diffusional equilibration of the O₂ local concentration with the bulk solution, then reactivating luciferase. Reversible inhibition-activation of luciferase was obtained upon cyclic application and releasing of the potential, respectively.