Sensitive detection of lincomycin based on ECL resonance energy transfer between Ir complex nanosheets and gold nanoparticles decorated Cu2O nanocomposites

In the present work, the nanosheets of iridium complex (Ir NS) were synthesized by surfactant assisted reprecipitation method. Strong anodic ECL signal of Ir NS was obtained under neutral aqueous condition with electrogenerated hydroxyl radical as coreactant, without the need of additional coreactant. Excellent light absorption ability of gold nanoparticles decorated Cu 2 O cubic nanoparticles (Cu 2 O@Au) could apparently inhibit the ECL intensity of Ir NS. When Cu 2 O@Au was assembled onto the electrode surface by base pair complementarity of DNA, the ECL resonance energy transfer (ECL-RET) system could be fabricated with Ir NS ECL as energy donor and Cu 2 O@Au as energy acceptor. The specific interaction of lincomycin (LIN) with the aptamer could release Cu 2 O@Au from the electrode surface, resulting in the recovery of ECL signal. Based on this, an “off-on” mode ECL sensor was designed to detect LIN. Under the optimal condition, the ECL intensity changed linearly with the logarithm of LIN concentration in the range of 1.0 × 10 −11 –1.0 × 10 −6  mol L −1 with a detection limit of 2.88 × 10 −13  mol L −1 . Importantly, the proposed ECL sensor showed outstanding accuracy and specificity in the detection of LIN, and provided a potential strategy for the determination of antibiotic.