In this work, Ru(phen)2(cpaphen)2þ linked-ampicillin (Ru-Amp), as the novel specific recognition element,
was proposed to construct a simple and sensitive electrogenerated chemiluminescence (ECL)
biosensor for the determination of β-lactamase. Here, Ru-Amp complex acted not only as a novel specific
recognition element for β-lactamase but also as the ECL Luminescent reagent. Through electrostatic
adsorption and the intermolecular π–π interactions, a large amount of Ru-Amp was immobilized to gold
nanoparticles (TA@AuNPs) prepared by thiophenemalonic acid (TA) to obtain Ru-Amp/TA@AuNPs nanocomposites.
The nanocomposites, which can produce very stable films exhibiting excellent ECL behaviors,
were self-assembled on the CNTs-Nf modified glassy carbon electrode surface. The presence of
the target β-lactamase resulted in autonomous hydrolysis reaction of Amp, achievement of the efficient
ECL emission and highly sensitive detection of β-lactamase. The biosensor for β-lactamase detection was
developed with excellent sensitivity of a concentration variation from 50 pg mL1 to 100 ng mL1 with a
low detection limit of 37 pg mL1
. An ECL assay offers the proposed method opportunities for designing
new Ru-based ECL luminophores for biosensing applications.
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