tHeavy metal ions are major contaminants in present day water supply. In this work the fabrication andevaluation of a DNAzyme functionalized capacitive micromechanical sensor array for the detection oflead ions is presented. The catalytic strand of a “8–17” DNAzyme can cleave a substrate DNA strand thathas one ribonucleotide base, in the presence of Pb2+, dissociating the complex into three fragments. TheDNAzyme strand is laser printed and immobilized on the sensor surface and hybridized with the substratestrand. When self-cleaving occurs, the surface stress changes, which is then registered as change in thecapacitance of the device. The sensor was able to detect 10 M of Pb2+, whilst in a reverse procedurethe re-hybridization of the immobilized catalytic strand with the substrate strand was demonstrated.The reactions were validated by tagging the catalytic strand with FAM (6-carboxyfluorescein), while thesubstrate strand was tagged with Dabcyl, a quencher.