Following ligation, copies are bound to immobilized templates by H-bridges between Watson-Crick base pairs. Dehybridization is a chemical operation which cleaves these H-bonds. Cleavage of H-bonds is most effectively achieved by applying a pulse of alkaline conditions (pH12) causing the deprotonation of T(U) and G’s at their imide or amidine moieties. Pulse generation can either take place by a localized electrolysis of water or the reduction of quinones absorbed on a microelectrode. The reduced quinone will uptake protons from water thus releasing a hydroxide signal which diffuses into the matrix causing copy liberation while leaving the original immobilized.