Fluorescein Isothiocyanate (FITC) is a green fluorescent dye widely used for protein labeling, antibody conjugation, and fluorescence-based biological research. It features a reactive isothiocyanate group that covalently binds primary amines to form stable thiourea linkages. Its bright green fluorescence supports flow cytometry, fluorescence microscopy, and biomolecular detection. Additionally, FITC enables fluorescent labeling of peptides, proteins, and other amine-containing molecules for cellular imaging and biochemical assays.
Key Features and Benefits
- Green Fluorescent Dye: Exhibits typical excitation near 495 nm and emission near 519 nm, providing green fluorescence for molecular detection.
- Reactive Isothiocyanate Group: Enables covalent labeling of primary amines, including lysine residues and accessible N-terminal amino groups in proteins.
- Stable Thiourea Bond Formation: Reacts with suitable primary amines to form covalent thiourea linkages for fluorescent biomolecular conjugation.
- High Fluorescence Intensity: Provides strong fluorescence in compatible environments, although signal intensity varies with pH and experimental conditions.
- Protein Labeling Capability: Specifically supports fluorescent modification of antibodies, peptides, and other amine-containing biomolecules.
- 488 nm Laser Compatibility: Supports excitation using blue lasers commonly available in flow cytometry and fluorescence imaging systems.
- Multicolor Fluorescence Compatibility: Enables combination with suitable fluorophores in multicolor imaging and flow cytometry experiments.
- Bioconjugation Versatility: Supports labeling of proteins, amino-functionalized polymers, and other molecules containing accessible primary amines.
- Research Flexibility: Additionally, enables development of fluorescent molecular probes for immunoassays, cellular imaging, and biomolecular interaction studies.
Applications
- Fluorescent Protein Labeling: Enables covalent attachment of green fluorescent dye molecules to proteins containing accessible primary amines.
- Antibody Conjugation: Supports preparation of FITC-labeled antibodies for immunofluorescence, flow cytometry, and antigen detection.
- Flow Cytometry: Provides green fluorescent conjugates for cellular marker detection and multiparameter analysis.
- Fluorescence Microscopy: Specifically supports visualization of fluorescently labeled biomolecules in compatible cellular and tissue imaging systems.
- Peptide Labeling: Enables fluorescent modification of peptides containing suitable reactive amino groups.
- Immunofluorescence Assays: Supports preparation of fluorescent antibody conjugates for detecting specific proteins and antigens in biological samples.
- Cellular Uptake Studies: Facilitates investigation of cellular internalization and distribution of FITC-labeled biomolecules.
- Biomolecular Interaction Research: Additionally, supports studies of protein localization, molecular binding, and biomolecular interactions using fluorescence detection.
- Fluorescence-Based Assay Development: Provides a reactive fluorescent reagent for developing analytical assays, molecular probes, and protein detection methods.
Storage and Handling
- Storage: Store at −20°C in a dry, tightly sealed container, protected from light and moisture. Additionally, minimize temperature fluctuations to preserve dye stability and isothiocyanate reactivity.
- Handling: Use clean, dry equipment and appropriate protective gear. Prepare fresh stock solutions in anhydrous DMSO or DMF, protecting the dye from light and moisture.
- Bioconjugation: React with primary amines in a compatible, amine-free buffer, typically at pH 8–9. Subsequently, optimize dye-to-protein ratios and reaction conditions while avoiding competing primary amines.
- Purification and Analysis: Remove unreacted dye using desalting, dialysis, or chromatography. Evaluate labeling efficiency, fluorescence intensity, and conjugate purity using appropriate analytical methods.
Fluorescein Isothiocyanate (FITC) combines strong green fluorescence with amine-reactive isothiocyanate chemistry for covalent biomolecular labeling. Its reactive functionality supports fluorescent modification of proteins, antibodies, peptides, and other amine-containing compounds. Therefore, it provides a versatile labeling reagent for flow cytometry, fluorescence microscopy, immunoassays, and cellular imaging research.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.
