National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan, 430079, P. R. China.
Hubei Key Laboratory of Plasma Chemistry and Advanced Materials, School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, 430205, P. R. China.
Angew Chem Int Ed Engl. 2023 Jul 17;62(29):e202304625. doi: 10.1002/anie.202304625. Epub 2023 Jun 12.
Exploring advanced co-reaction accelerators with superior oxygen reduction activity that generate rich reactive oxygen species (ROS) has attracted great attention in boosting luminol-O electrochemiluminescence (ECL). However, tuning accelerators for efficient and selective catalytic O activation to switch anodic/cathodic ECL is very challenging. Herein, we report that enzyme-inspired Fe-based single-atom catalysts with axial N/C coordination structures (FeN , FeN © SACs) can generate specific ROS for cathodic/anodic ECL conversion. Mechanistic studies reveal that FeN sites prefer to produce highly active hydroxyl radicals and afford direct cathodic luminescence by promoting the cleavage of O-O bonds through N-induced electron redistribution. In contrast, FeN © sites tend to produce superoxide radicals, resulting in inefficient anodic ECL. Benefiting from the enhanced cathodic ECL, FeN SAC-based immunosensor was constructed for the sensitive detection of cancer biomarkers.
探索具有优越氧还原活性的先进共反应加速剂，以产生丰富的活性氧物种 (ROS)，这在促进鲁米诺-O 电化学发光 (ECL) 方面引起了极大关注。然而，调节加速剂以实现高效和选择性的 O 活化以切换阳极/阴极 ECL 是极具挑战性的。在此，我们报告了受酶启发的具有轴向 N/C 配位结构的基于 Fe 的单原子催化剂 (FeN 、FeN © SACs) 可产生特定的 ROS，用于阴极/阳极 ECL 转化。机理研究表明，FeN 位点通过 N 诱导的电子重排促进 O-O 键的断裂，更倾向于产生高活性的羟基自由基，并通过促进 O-O 键的断裂提供直接的阴极发光。相比之下，FeN © 位点倾向于产生超氧自由基，导致阳极 ECL 效率低下。受益于增强的阴极 ECL，构建了基于 FeN SAC 的免疫传感器，用于灵敏检测癌症生物标志物。
