An electrochemiluminescence insulin sensing platform based on the molecular recognition properties of cucurbit[7]uril

The establishment of new mechanisms for target identification and signal amplification continues to drive innovation in electrochemiluminescence (ECL) sensing platforms. In this paper, a novel ECL insulin sensing platform was constructed by utilizing the molecular recognition properties of cucurbit[7]uril. Specifically, the macrocyclic host molecule cucurbit[7]uril was immobilized on the surface of the sensing platform as an identification probe, which could selectively capture insulin according to the inherent properties of the protein Nterminal. Introducing the rigid molecule cucurbit[7]uril into the sensing interface could reduce the influence of the environmental parameters on the sensing system, which provides a reliable guarantee for the accurate detection of insulin. Furthermore, gold nanoclusters were modified by utilizing the molecular recognition properties of cucurbit[7]uril, and used as anode signal probes for ECL sensing platform. The macrocyclic molecules cucurbit[7]uril passivated the surface of the nanoclusters, inhibited the non-radiative relaxation and improved the physical stability of the luminophore, leading to a significant increase in the sensitivity and stability of the ECL probe. The ECL sensing platforms exhibited a linear range from 50.00 fg/mL to 100.0 ng/mL, with a detection limit of 5.44 fg/mL. This study revealed the critical role of cucurbit[7]uril in target recognition and signal amplification, extending the scope of supramolecular applications in ECL.