# Electrolysis in Electrophoresis of proteins and DNA

Can electrolysis happen in an electrophoresis assay (such as SDS-PAGE)? To perform electrophoresis, the substances must be dissolved in an aquatic buffer with a previously determined ionic strength. One might expect to see $$\ce{H2}$$ and $$\ce{O2}$$ on each side of the electrodes as well as $$\ce{H2}$$ and $$\ce{Cl2}$$ (resulting from electrolysis of $$\ce{H2O}$$ and $$\ce{NaCl}$$ respectively). Does this actually happen or it is somehow prohibited in the experiment? If yes, then how do manufacturers reduce the effects of such additional reactions in the electrophoresis apparatus? If no, what principles of electrochemistry have I forgotten to consider?