Fluorescein derivatives are the most common fluorescent reagents for biological research because of their high absorptivity, excellent fluorescence quantum yield, and good water solubility.
Fluorescein-based dyes and their conjugates have several performance characteristics that may facilitate or limit use in certain applications. Fluorescein displays:
|We offer a broad range of fluorescein conjugates and derivatives as well as a series of high-performance fluorophores with improved characteristics for labeling and detection.|
|Fluorescein is a bright green fluorphore that is sensitive to changes in pH and can photobleach rapidly unless an antifade agent is used. Anti-fluorescein antibodies can be useful in amplifying a weak signal.|
Photostability in buffer
Photostability in antifade
We offer a broad range of fluorescein products including protein and antibody labeling kits, primary and secondary antibody conjugates, bioconjugates, and more.
Learn more here:
- Antibody and protein labeling kits
- Primary antibodies
- Secondary antibodies
- Streptavidin conjugates for signal amplification
HeLa cells were fixed and permeabilized using several Invitrogen products Image-iT Fixation/Permeabilization Kit then incubated with Anti-ATP Synthase Subunit IF1 and GAM-FITC secondary Ab. Cells were counterstained with NucBlue Live and ActinRed 555 then mounted using ProLong Gold Antifade Mountant and imaged using the EVOS M7000 Imaging System and a EVOS 40X Objective, coverslip-corrected
Fluorescein reactive dyes
Select dye-labeling chemistries for conjugation with the following reactive groups:
Fluorescein protein/antibody labeling kits
Select an optimized labeling kit for your target antibody or protein:
High-performance alternatives to fluorescein
The Invitrogen Molecular Probes Alexa Fluor 488 dye—with spectral properties and quantum yield nearly identical to those of fluorescein isothiocyanate (FITC)—produces brighter, more photostable conjugates. These conjugates are ideal for imaging and other applications requiring increased sensitivity and environmentally insensitive fluorescence detection.
For pH monitoring the Invitrogen Molecular Probes pHrodo Green dye is almost nonfluorescent at neutral pH and fluoresces brightly in acidic environments. Unlike fluorescein, the minimal dye fluorescence at neutral pH also eliminates the need for wash steps and quencher dyes because any non-internalized dye will be essentially nonfluorescent.
|Comparison of the relative fluorescence of goat anti–mouse IgG antibody conjugates prepared from Alexa Fluor 488 dye and from fluorescein isothiocyanate (FITC). Conjugate fluorescence is determined by measuring the fluorescence quantum yield of the conjugated dye relative to that of a reference dye and multiplying by the dye:protein labeling ratio.|
5 steps resources
Not for resale. Super Bright Polymer Dyes are sold under license from Becton, Dickinson and Company.
For Research Use Only. Not for use in diagnostic procedures.