The AgCNS was prepared by an extremely simple and environmental one-pot method.

AgCNS was an innovative luminophore with excellent ECL performance.

It is a new attempt of g-C3N4 based MOGs in the field of ECL sensor.

THS was firstly used in the fabrication of ECL aptasensor for AβOs analysis.

The synergistic strategy offers a new opportunity for clinical application.

Amyloid-β oligomers (AβOs) was the core-biomarker of Alzheimer's disease (AD), and the detection of AβOs is very important for the early diagnosis of AD. However, existing tests for AβOs are majorly suffering from complex process and poor sensitivity. Thus, an adjustable AβOs electrochemiluminescence (ECL) aptasensor based on the synergistic effect of self-enhanced metal-organic gel (AgCNS) and triple-helix DNA system (THS) was successfully constructed. AgCNS was prepared by an extremely simple one-pot method and was an innovative luminophore with excellent ECL performance. The AgCNS-labeled complementary sequence ([email protected]) was interlaced with the unlabeled aptamer (Apt) carrying two short-arms fixed on the gold electrode (GE) to form the THS. Along with the specific-binding of AβOs and Apt, the THS was disrupted and adjusted flexibly between “on” and “off”, resulting in significant changes in the ECL signals. Thus, ECL detection of AβOs was sensitively achieved with a detection limit as low as 0.23 fM and the different forms of Aβ can be specifically distinguished. The aptasensor also exhibited satisfactory selectivity, stability and reproducibility. Moreover, when proposed method and ELISA-kit were simultaneously applied to artificial cerebrospinal fluid (A-CSF) samples, the obtained results were completely consistent, reflecting the potential clinical application value of this work.

Amyloid-β oligomers

Electrochemiluminescence aptasensor

Metal-organic gel

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