Electrochemical sensing devices using ATCUN-Cu(II) complexes as electrocatalysts for water oxidation

This work demonstrated that electrochemical sensing devices can be fabricated by electrocatalytic water oxidation. First, we suggested that the Cu(II) complexes with amino terminal Cu(II)- and Ni(II)-binding (ATCUN) peptides showed good electrocatalytic ability toward water oxidation. In contrast to the previously reported electrocatalysts for water oxidation, the ATCUN-Cu(II) electrocatalysts can operate at neural pH with lower oxidation potential. Furthermore, the ATCUN-Cu(II) metallopeptides can be easily modified onto the surface of nanomaterials to produce nanocatalysts for water oxidation. To demonstrate the analytical performances of the ATCUN-Cu(II) electrocatalysts as electrochemical signal labels, DNA analysis was performed in a sandwich option using gold nanoparticles (AuNPs) as the carriers. The method detected DNA down to 0.1 pM. This is the first time that H 2 O molecule was employed as the electrocatalytic substrate in electrochemical sensing devices.