Active Motif,
Tools to analyze nuclear function,
Your CartYour Cart 0 items


Sign up to receive new product updates
and promotional pricing.


Chromeo™ Red Fluorescent Fixed Cell Staining Kit

effective fluorescent cell stain for immunofluorescence experiments

The Chromeo™ Red Fluorescent Fixed Cell Staining Kit is based on a proprietary dye that stains the nuclear membrane, mitochondria, fibers and nucleoli in fixed cells. In parallel, the nuclei can be stained with DAPI, which is also included in the kit. The combination of cellular and nuclear staining is ideal for use as a counterstain in immunofluorescence experiments in combination with FITC or other 488 nm excitable fluorescent dyes like Chromeo™ 488. In addition, the kit can be used to monitor changes in the localization and shape of nuclei, to highlight changes in cellular morphology and to monitor cell-cell contacts within a population of cells. The kit is suitable for use in both fluorescence microscopy and high-content screening (HCS).

HeLa cells stained using the Chromeo Red Fluorescent Fixed Cell Staining Kit and Chromeo 488 Fluorescent Secondary Antibody
Figure 1: Staining of fixed HeLa cells using the Chromeo Red Fluorescent Fixed Cell Staining Kit and Chromeo 488.

HeLa cells were stained with alpha Tubulin mouse mAb (Clone 5-B-1-2) and Chromeo 488 Goat anti-mouse IgG (Catalog No. 15031). The Chromeo Red Fluorescent Fixed Cell Staining Kit was used for counterstaining cellular structures (red) and the nuclei (blue).

Name Format Cat No. Price  
Chromeo™ Red Fluorescent Fixed Cell Staining Kit 1 kit 15006 $240 Buy Now

The Chromeo™ Red Fluorescent Fixed Cell Staining Kit contains a unique dye that is not fluorescent until after it has reacted with an amino group; this causes a structural change in the dye, resulting in bright red fluorescence. In fixed cells, the stain typically reacts with structures in mitochondria, fibers, nuclear membranes and nucleoli. A long Stokes shift separates the excitation wavelength of 540 nm from the emission maximum at 627 nm. Because the emission wavelength is shifted so far, the dye can be used in co-staining experiments with GFP, FITC and most other 488 nm excitable dyes without any interference or overlap between the red and green signals.

If the stain is used in multi-color experiments with Fluorescent Secondary Antibody Conjugates, the cell staining is performed as part of the regular staining procedure, which eliminates the need for additional incubation and washing steps. This saves time during co-staining experiments in fluorescence microscopy or in high-content screening experiments (HCS).

The included MAXfluor™ DAPI Mounting Medium contains the widely used nucleic acid stain and provides optimal fluorescence stability, superior anti-fading during long-term storage, and inhibition of photobleaching during examination by both traditional (single photon excitation) and super-resolution microscopy (4Pi). The effect of MAXfluor Mounting medium can vary depending on the structure of the dye being used. MAXfluor is recommended for use with Fluorescein and Chromeo 488, but it has been shown to cause photobleaching of Alexa 488 conjugated antibodies.

Chromeo Red Fluorescent Cell Stain advantages

  • Water soluble fluorescent fixed cell stain
  • Fluoresces after interaction with proteins, which eliminates background
  • DAPI staining of the nucleus
  • Mounting Medium provides optimal fluorescent stability
  • Ideal for multiplexing with 488-excitable dyes

The dyes included in the Chromeo™ Red Fluorescent Fixed Cell Staining Kit can be excited with commonly used excitation sources and standard filter sets of fluorescent microscopes or readers. The cellular stain can be excited between 520 nm and 550 nm (max at 540 nm) and emits at 627 nm. This long Stokes shift separates the emission spectrum of the cellular stain from the emission spectra of GFP or 488 nm excitable dyes, which enables co-staining experiments. The broad emission spectrum of the stain allows flexibility and optimal intensity in detection. The DAPI nuclear stain has its excitation maximum at 358 nm and emission maximum at 461 nm. DAPI filter sets are available in most fluorescence microscopes and fluorescent plate readers.

Contents & Storage

  • 1 vial of lyphilized Chromeo™ Red Fluorescent Fixed Cell Stain (store at -20°C in the dark)
  • 1 vial DMF (store at 4°C)
  • 2 vials  MAXfluor™ DAPI Mounting Medium (store at 4°C in the dark)

Contents guaranteed 6 months when stored properly.

The kit is designed to stain 260 slides based on the use of 22 mm square coverslips, or 2500 wells in 8-well chambered slides, or 5000 wells in a 96-well plate. The number of experiments will depend on the chosen concentration of the stain, which may vary for different cell types.