In situ monitoring reactive oxygen species released by single cells using scanning electrochemical microscopy with A Specifically designed multi-potential step waveform

Abstract

Reactive oxygen species (ROS) have gained much attention as they are related to cellular homeostasis and functions. New insights into physiology of cancer cells are anticipated from the analysis of their ROS evolution at single cancer cells level. Herein, a novel scanning electrochemical microscopy (SECM) detection strategy with a specifically designed multi-potential step waveform (MPSW) has been developed for in situ monitoring ROS with no interference of dissolved oxygen (DO) at the single cells level. Using MPSW, the signals of three different electrochemical molecules – FcMeOH, DO and ROS could be obtained simultaneously in a single imaging process. Images of FcMeOH were used to determine cell morphology. ROS released by normal and cancer cells without the interference of DO were imaged and quantitatively determined using MPSW. ROS released by cancer cells under different pHs was further investigated, suggesting that an acid environment could stimulate the release of ROS. Thus, this work provides a new way for sensing ROS released by cells without interference, and can be applied in the cancer research based on ROS releasing.