Features of NucBlue® Fixed Cell ReadyProbes™ Reagent:
- Ready-to-use liquid DAPI formulation
- No need to dilute, weigh, or pipette
- Convenient dropper bottle—just use two drops per ml
- Stable at room temperature—keep handy at your scope or cell culture area
DAPI is a classic fluorescent dye used extensively for nuclear staining of fixed cells. In fluorescence microscopy, DAPI is excited with UV light and detected through a blue/cyan filter (Figure 1).
Packaged for Convenience
DAPI is typically supplied as a solid that requires weighing out and diluting several thousand-fold before use. The recommended storage is generally in a freezer or refrigerator. The NucBlue® Fixed Cell Stain formulation of this imaging workhorse reagent is ready to use and can be stored right next to your microscope or workstation. A liquid formulation in an ultra-convenient dropper bottle allows you to counterstain your cells whenever and wherever they are ready. Just add two drops per ml for optimally bright and distinct nuclear labeling.
The spectral properties of DAPI (4',6-diamidino-2-phenylindole), its selectivity for dsDNA, and its increase in fluorescence when bound to DNA make it an excellent fluorescent nuclear counterstain ideal for use with green (Alexa Fluor® 488, FITC, GFP) and red (Alexa Fluor® 594, rhodamine, Texas Red®, mCherry, mKate-2) fluorophores in multicolor experiments. Because of its high affinity to DNA, it is also frequently used for counting cells, measuring apoptosis, sorting cells based on DNA content, and as a nuclear segmentation tool in high content imaging analysis.
Suggestions for Use:
- In most cases 2 drops/ml of NucBlue® Fixed Cell Stain and an incubation of 15 to 30 minutes will produce bright nuclear staining; however, optimization may be needed for some cell types, conditions, and applications. In such cases, simply add more, or fewer, drops until the optimal staining intensity is obtained.
- NucBlue® Fixed Cell Stain is excited by UV light at 360 nm when bound to DNA, with an emission maximum at 460 nm. It is detected through a blue/cyan filter, such as a DAPI filter, blue GFP filters, or the Semrock BrightLine® Alexa Fluor® 350 Dye filter set.
- As a preferred blue nuclear stain in fixed cell imaging experiments, NucBlue® Fixed Cell Stain is ideal for use with antibody-based applications.