Following the validation of the method to calculate the proton concentration with the Faradaic currents, we deployed the platf orm for the control of acidity in organic solvents using ACN. Since FAM bares 2 carboxylic radicals, to avoid reactions with the amino groups of the 4-ATP in the electrodes we introduced a coating layer with a perf luorinated sulfonate polymer (Naf ion 117). Naf ion in addition to protect the 4-ATP groups, it can transport the electrochemically generated protons f rom the electrodes to the solution through its sulfonate channels. Figure The Faradaic currents show two peaks that we ascribe to the oxidation of the dimerized and monomer forms of 4-ATP at ~0.3V and ~0.55V, respectively. These peaks were persistent; thus, we believe that the Naf ion coating avoids f urther polymerization. The oxidation peaks are also shif ted towards higher bias, as it is expected due to the increas e of the pK a of the electrolyte. We also observe an inc rease of the bias for the reduction peak, co nsequent with this eff ect. The Faradaic currents were extracted f rom each voltammogram cycle to calculate the number of protons produced during each bias ramp (more details of the extraction shown in SI-4 Table ). The concentration of the protons produced during the oxidation (1,67.10 -2 M) is almost equivalent to ones re-adsorbed for the reduction (1,45.10 -2 M). The concentration of protons (log(Q/F*V)) and the relative f luorescence normalized to the maximum value in normal conditions are shown vs time in the inset of Figure .