An ultra-sensitive electrochemiluminescence probe based on ternary nanocomposite and boron nitride quantum dots for detection of diazinon.

A new enzyme-free electrochemiluminescence (ECL) pesticide sensor was fabricated based on ternary nanocomposite of ruthenium nanoparticles/silver nanoparticles/graphene oxide on the surface of glassy carbon electrode for ultratrace determination of diazinon. Due to some drawbacks of enzyme-based sensors such as enzyme instability at elevated temperature, humidity, changes of pH, and high price of the enzyme, the use of enzyme was omitted in the construction of the developed sensor. The silver nanoparticles with good electrocatalytic proficiency as a signal improving agent and tris(2,2bipyridine) ruthenium(II) as a popular luminophore were uniformly deposited on the surface of the prepared graphene oxide/GC electrode at nanoscale. Boron nitride quantum dots as an efficient co-reactant created the superior efficiency in amplifying the ECL intensity of the ruthenium-based ECL system. The prepared electrode was utilized for the detection of diazinon via the robust ECL method. For the present sensor, a wide linear dynamic range and low detection limit were achieved (3.0 × 10-15 to 6.5 × 10-9 M and 9.5 × 10-16 M, respectively). The obtained results confirmed the fabrication of the robust ECL probe, which is characterized by the cooperative effect of silver nanoparticles and the attached luminophore species. The main advantage of the presented sensor was that the samples could be diluted so that the effect of the interference species was negligible. Due to excellent properties toward accurate determination of diazinon, the ECL sensor as a new practical platform was applied for quantitative detection of diazinon in some real samples.