CM-H2DCFDA (General Oxidative Stress Indicator) - FAQs

View additional product information for CM-H2DCFDA (General Oxidative Stress Indicator) - FAQs (C6827)

5 product FAQs found

I want to assay cells for reactive oxygen species using carboxy-H2DCFDA, but I want to do so with a plate reader instead of microscope. Will it work?

It has been done. The problem is that plate readers are less sensitive than microscopes, with far less signal-to-background difference. It is worth trying, but first optimize concentrations and loading times with control cells, use a plate with little to no autofluorescence, and possibly optimize the gain setting in order to get the best signal possible. But don't expect the same sensitivity, even with optimization.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

I have GFP-transfected cells and need to label for reactive oxygen species. Can I use H2DCFDA?

This is not recommended as the two dyes overlap in the emission wavelength. There are other ROS reagents available in different wavelengths, such as CellROX Deep Red, which emits in the far-red range (665 nm), or dihydroethidium, which is emits in the visible red range (620 nm).

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

I labeled my cell with CM-H2DCFDA for reactive oxygen detection, but upon illuminating the cell there is a significant increase in fluorescence in the control cells. Why?

If the cell is overloaded with dye, the high intracellular concentration of the dye may lead to dye-dye quenching. Upon illumination, photobleaching will occur, which will reduce the dye-dye quenching and actually increase the fluorescence (for a while, but then it will start decreasing). To solve the problem, reduce the concentration and incubation time, and try a range of incubation times and concentrations.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

I need a formaldehyde-fixable reactive oxygen species detection assay. Is H2 DCFDA fixable?

H2DCFDA and similar derivatives are not fixable. The same goes for dihydroethidium and dihydrorhodamine. However, CellROX Deep Red and CellROX Green are retained for a limited time upon fixation with formaldehyde. CellROX Green may be retained upon subsequent Triton X-100 permeabilization. Avoid the use of any acetone or alcohol-based fixatives or fixatives that include alcohol, such as formalin.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

Why don't I see a significant change in signal for my live-cell fluorescent indicator dye?

Regardless of the type of live-cell indicator dye (e.g., calcium indicators, pH indicator, metal ion indicators), make sure there is no serum during the loading step, which can prematurely cleave dyes with AM esters and bind dyes non-specifically. Always optimize the dye concentration and staining time with a positive control before you run your test samples, to give the best signal-to-background. Always run a positive control with a buffer containing free ions of known concentration and an ionophore to open pores to those ions (for instance, for calcium indicators like Fluo-4 AM, this would include a buffer with added calcium combined with calcimycin, or for pH indicators, buffers of different pHs combined with nigericin). Reactive oxygen indicators, such as CellROX Green or H2DCFDA would require a cellular reactive oxygen species (ROS) stimulant as a positive control, such as menadione. Finally, make sure your imaging system has a sensitive detector. Plate readers, for instance, have much lower detector efficiency over background, compared to microscopy or flow cytometry.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.