Simultaneous determination of NO released inside and outside cells at the single-cell level using CE-LIF.

A simple, fast and reliable method based on capillary electrophoresis (CE) coupled with laser-induced fluorescence (LIF) detection was developed for the simultaneous analysis of NO released both inside and outside cells at the single-cell level closer to physiological conditions. After pre-capillary dual-labeling derivatization with a group of cells, single cells were injected into the separation capillary and lysed. The subsequent separation and detection of NO derivatives were achieved within 4.0 min producing mass limits of detection of 3.0 and 10.7 amol for intra- and extracellular NO, respectively. The developed method was successfully applied for simultaneous measurement of NO released both inside and outside single RAW 264.7 macrophage cells.