Electrochemical Monitoring of ROS/RNS Homeostasis Within Individual Phagolysosomes Inside Single Macrophages

Abstract

The existence of a homeostatic mechanism regulating reactive oxygen/nitrogen species (ROS/RNS) amounts inside phagolysosomes has been invoked to account for the efficiency of this process but could not be unambiguously documented. Now, intracellular electrochemical analysis with platinized nanowire electrodes (Pt‐NWEs) allowed monitoring ROS/RNS effluxes with sub‐millisecond resolution from individual phagolysosomes impacting onto the electrode inserted inside a living macrophage. This shows for the first time that the consumption of ROS/RNS by their oxidation at the nanoelectrode surface stimulates the production of significant ROS/RNS amounts inside phagolysosomes. These results establish the existence of the long‐postulated ROS/RNS homeostasis and allows its kinetics and efficiency to be quantified. ROS/RNS concentrations may then be maintained at sufficiently high levels for sustaining proper pathogen digestion rates without endangering the macrophage internal structures.

Chemical Analysis of Single Cells and Organelles

“…Later, Zhang et al measured ROS/RNS effluxes from individual phagolysosomes with IVIEC at platinized nanowire electrodes (Pt-NWEs) with submillisecond resolution. 15 Both works confirmed the existence of ROS/RNS homeostasis and helped to unravel the complexity of phagocytosis. Pan et al carried out electrochemical resistive-pulse experiments inside a RAW 264.7 macrophage cell with platinized open carbon nanopipettes (CNPs) to sample single vesicles and measure ROS/RNS contained inside them.…”

Construction of micro-nano electrochemical sensing interfaces for real-time monitoring of single cells

“…(A)CFNE电镜表征图(a)电极插入突触间隙明场照片(b), 高钾刺激 后安培信号图及"简单峰"和"复杂峰"信号放大图(c) [77] ; (B)CFNE插入DA神经元突触明场照片(a), 未处理DA神经元及哈巴 苷、6-OHDA、哈巴苷预处理后6-OHDA孵育条件下DA神经元胞吐释放多巴胺分子电量统计图(b), CFNE检测药物调控下 DA神经元突触间隙胞吐释放的示意图及猜测机理(c) [82] (网络版彩图) 监测. 实验结果表明, 50%以上的事件具有"复杂峰"信 号特征 (图6(A-c) 降阶段出现明显的拖尾(图7(A-c)) [20] . [84,85] .…”

Trendbericht Analytische Chemie II: Trenntechniken und Elektroanalytik

“…Diese Aspekte spielen nach wie vor eine Rolle. 31) In letzter Zeit sind allerdings zunehmend analytische Charakterisierungen von anorganischen Materialien mit hoher Auflösung gefragt. Das trifft insbesondere auf Materialkomposite mit elektrokatalytischen Eigenschaften zu.…”