Under-Operando Spectroelectrochemical Visualization of pH Changes Electrogenerated in the Pulsed Electric Field

Pulsed electric field (PEF) has rapidly growing applications in medicine, the food industry, and biotechnology. PEF acts on biomolecules in target samples via several interwoven mechanisms,\nbeing far from completely understood. In electrically conductive samples, charge transfer reactions occur at electrode/sample interfaces, which have several kinds of chemical consequences, including pH gradients. In this work, we develop a spectroelectrochemical (SEC) technique based on the employment of colorimetric indicators to track pH changes generated by PEF, separately for anode and cathode. We demonstrate that pulse architecture has a decisive influence on the pH changes in the sample subjected to PEF.