There is disclosed an electrode array architecture employing continuous and discontinuous circumferential electrodes. There is further disclosed a process for the neutralization of acid generated at anode(s) by base generated at cathode(s) circumferentially located to each other so as to confine a region of pH change. The cathodes can be displayed as concentric rings (continuous) or as counter electrodes in a cross pattern (discontinuous). In this way reagents, such as acid, generated in a center electrode are countered (neutralized) by reagents, such as base, generated at the corners or at the outer ring.