A new impedimetric sensor based on anionic intercalator for detection of lead ions with low cost and high sensitivity

The graphical abstract is preparation of impedimetric sensor. The high specificity of GR-5 DNAzyme fixed on gold interdigitated electrodes (GID), which made on printed circuit board (PCB) is cost-effective. The anionic intercalator anthraquinone-2-sulfonic acid (AQMS) intercalated into the base-pairing regions of GR-5 DNAzyme as the signal amplification. In the presence of Pb2+ ions, the GR-5 DNAzyme was cleaved into two parts at the RNA site (rA), which results in the releasing of AQMS from the GR-5 DNAzyme. The anionic intercalator can promote electron transfer without interfering signals, which enhanced the performance of the sensor obviously.78