Supramolecular Anchored Copper Nanoclusters for a Multipath Electrochemiluminescence Probe

Copper nanoclusters (Cu NCs) are highly promising nanomaterials in the field of electrochemiluminescence (ECL). Nevertheless, their limited stability and efficiency have impeded their practical applications. Here, we introduced a novel supramolecular anchoring strategy resulting in the creation of exceptionally stable Cu NCs (CET-Cu NCs) with remarkable ECL properties. Specifically, CET-Cu NCs exhibited a relative ECL efficiency (Φ_ECL) of 62% based on the annihilation ECL efficiency of [Ru(bpy)₃]²⁺ (100%), with tripropylamine employed as a coreactant. Moreover, CET-Cu NCs can generate ECL emission through multiple different paths, which enables them to serve as signal probes in a wider range of testing scenarios, thereby enhancing the reliability and robustness of sensing and analytical systems. To demonstrate the practical utility, CET-Cu NCs were selected as an ECL signal probe for a sensing platform that facilitated ultrasensitive detection of progesterone via oriented immobilization technology and antibody/aptamer sandwich assays. This study surmounted the barriers to the practical application of Cu NCs through the implementation of a supramolecular anchoring strategy, thereby providing enhanced utility of Cu NCs in ECL sensing and analysis.