Potential-Resolved
Ratiometric Aptasensor for Sensitive
Acetamiprid Analysis Based on Coreactant-free Electrochemiluminescence
Luminophores of Gd-MOF and “Light Switch” Molecule of
[Ru(bpy)2dppz]2+
posted on 2024-03-12, 16:35authored byJingshuai Li, Yan Zhou, Mengzhen Xi, Liuyong Hu, Bingzhang Lu, Wenling Gu, Chengzhou Zhu
For conventional potential-resolved ratiometric electrochemiluminescence
(ECL) systems, the introduction of multiplex coreactants is imperative.
However, the undesirable interactions between different coreactants
inevitably affect analytical accuracy and sensitivity. Herein, through
the coordination of aggregation-induced emission ligands with gadolinium
cations, the self-luminescent metal–organic framework (Gd-MOF)
is prepared and serves as a novel coreactant-free anodic ECL emitter.
By the intercalation of [Ru(bpy)2dppz]2+ with
light switch effect into DNA duplex, one high-efficiency cathodic
ECL probe is obtained using K2S2O8 as a coreactant. In the presence of acetamiprid, the strong affinity
between the target and its aptamer induces the release of [Ru(bpy)2dppz]2+, resulting in a decreasing cathode signal
and an increasing anode signal owing to the ECL resonance energy transfer
from Gd-MOF to [Ru(bpy)2dppz]2+. In this way,
an efficient dual-signal ECL aptasensor is constructed for the ratiometric
analysis of acetamiprid, exhibiting a remarkably low detection limit
of 0.033 pM. Strikingly, by using only one exogenous coreactant, the
cross interference from multiple coreactants can be eliminated, thus
improving the detection accuracy. The developed high-performance ECL
sensing platform is successfully applied to monitor the residual level
of acetamiprid in real samples, demonstrating its potential application
in the field of food security.