Monitoring and determination of ultra-trace concentrations of monoamine neurotransmitter such as noradrenaline (NA) in living cells with simple, sensitive and selective assays are significantly interesting. We design NA-electrode sensing system based on C-, N-doped NiO broccoli-like hierarchy (CNNB). The spherical broccoli-head umbrella architectures associated with nano-tubular arrangements enabled to tailor NA biosensor design. The homogenous doping and anisotropic dispersion of CN nanospheres along the entire NB head nanotubes lead to creating of abundant electroactive sites in the interior tubular vessels and outer surfaces for ultrasensitive detection of NA in living cells such as PC12. The CNNB biosensor electrodes showed efficient electrocatalytic activity, enhanced kinetics for electrooxidation of NA, and fast electron-transfer between electrode–electrolyte interface surfaces, enabling synergistic enhancement in sensitivity, and selectivity at a low-detectable concentration of ∼ 6 nM and reproducibility of broccoli-shaped NA-electrodes. The integrated CNNB biosensor electrodes showed evidence of monitoring and screening of NA released from PC12 cells under K⁺ ion-extracellular stimulation process. The unique features of CNNB in terms of NA-selectivity among multi-competitive components, long-term stability during the detection of NA may open their practical, in-vitro application for extracellular monoamine neurotransmitters detection in living cells.

用简单，灵敏和选择性的方法监测和测定活细胞中超痕量单胺神经递质（如去甲肾上腺素（NA）的浓度是非常有趣的。我们设计了基于C，N掺杂的NiO西兰花样层次（CNNB）的NA电极传感系统。球形西兰花头伞结构与纳米管排列相关，可定制NA生物传感器设计。CN纳米球沿整个NB头纳米管的均匀掺杂和各向异性分散，导致在内部管状容器和外表面中形成丰富的电活性位点，以超灵敏地检测活细胞（例如PC12）中的NA。CNNB生物传感器电极显示出有效的电催化活性，增强了NA电氧化的动力学，以及电极与电解质界面之间的快速电子转移，可协同提高灵敏度，并在低至6 nM的低检测浓度下具有选择性，并具有西兰花形NA电极的重现性。集成的CNNB生物传感器电极显示了监测和筛选在K下从PC12细胞释放的NA的证据。⁺离子细胞外刺激过程。CNNB在多种竞争成分之间的NA选择性，NA检测过程中的长期稳定性方面的独特功能，可能为活细胞中细胞外单胺神经递质的检测打开了它们在体外的实际应用。