Electrochemiluminescence Detection of Silver Ion Based on Trigeminal Structure of DNA

Abstract

A novel electrochemiluminescence (ECL) biosensor for highly sensitive and selective detection of Ag + is developed based on the sensitive "turn-on" structure-switching trigeminal structure of deoxyribonucleic acid (DNA-TS). DNA-TS consists of three oligonucleotides hybridized to form three double-stranded DNA like Y-shaped DNA structure. The formation of DNA-TS makes the ECL sign Ru(bpy) 2 (mcbpy-O-Su-ester)(PF 6 ) 2 of reporter probe approach to the electrode surface and thus increase the ECL signal intensity. The "signal-on" ECL biosensor could detect Ag + concentration in the range from 1.0 × 10 -11 to 3.2 × 10 -9 mol L -1 , and the limit of detection is 3.0 × 10 -12 mol L -1 . The strategy is sensitive and rapid. This approach could be extended to the design of sensors for other desired heavy metal ions as well. Such ECL sensors are promising for sensitive detection of other heavy metal ions.

Electrochemiluminescence Systems for Metal‐Ion Detection: A Systematic Review

“…This study utilized three probes: thiolated capture probe P1 that was selfassembled onto the Au electrode, Ru(bpy) 2 (mcbpy-O-Su-ester)(PF 6 ) 2 (Ru1) labeled probe P2, and auxiliary probe P3. [182] The trigeminal structure of DNA was formed by the interaction of C-Ag + -C between P1 and P2, making the luminophore Ru1 (P2) approach the surface of the Au electrode and thus increasing the ECL signal intensity. This system successfully detected Ag(I) concentration in the range of 10 pM-3.2 nM and the detection limit of 3.0 pM.…”