Double-enhanced sandwich electrochemiluminescence aptasensor based on g-C3N4–Au-luminol nanocomposites and ZnCuS nanosheets for highly sensitive detection of mucin 1

The traditional luminol electrochemiluminescence (ECL) sensing suffers from low signal response and instability issues. Here, an Au/ZnCuS double-enhanced g -C 3 N 4 -supported luminol ECL aptasensor is constructed for the sensitive detection of human mucin 1 (MUC1). In this platform, g -C 3 N 4 of a large specific surface area is beneficial to load more luminol illuminants. Au nanoparticles promote the decomposition of H 2 O 2 coreactants to generate more reactive oxygen (•OH and O 2 • − ) intermediates, while ZnCuS can immobilize the aptamer and simultaneously catalyze H 2 O 2 decomposition, realizing the double-wing signal amplification. Under optimal conditions, this sensor shows a good detection capability within 1.0 × 10 −4 –1.0 × 10 3  ng mL −1 and a low detection limit of 5.0 × 10 −5  ng mL −1 , as well as ideal stability, selectivity, and reproducibility. This double-enhanced aptasensor highlights a new signal-enhancement approach for early biomarker detection.