6-FAM-PEG3-Azide | CAS 412319-45-0

6-FAM-PEG3-Azide is a fluorescein (6-FAM)-labeled azide reagent designed for click chemistry-based fluorescent labeling workflows. The PEG3 spacer helps separate the dye from the biomolecule or surface to reduce steric effects, while the terminal azide enables efficient azide-alkyne cycloaddition for constructing fluorescent conjugates. Researchers use this reagent to introduce a bright, visible fluorophore handle into proteins, peptides, nucleic-acid constructs, and polymer or biomaterial surfaces for fluorescence microscopy and flow cytometry readouts.

1. Biomolecule Labeling

6-FAM-PEG3-Azide is frequently used by chemical biology and protein engineering groups to generate fluorescently tagged biomolecules via azide-alkyne click conjugation. In typical workflows, the azide functionality is installed on a protein, peptide, or affinity reagent (or used to label a biomolecule that has been equipped with a complementary alkyne handle), enabling downstream visualization of binding, trafficking, or interaction events. The PEG3 linker provides practical flexibility for labeling systems where the fluorophore needs spatial separation from the binding interface to maintain labeling consistency for fluorescence imaging and quantitative fluorescence readouts.

2. Fluorescent Probe Construction

6-FAM-PEG3-Azide supports fluorescent probe development where a defined fluorophore is appended to a targeting scaffold or recognition element using click-compatible modular chemistry. Common use cases include assembling fluorescent reporters for microscopy-based assays, building labeled affinity probes for binding studies, and preparing traceable conjugates for reagent characterization. The fluorescein dye provides a widely adopted excitation/emission profile that fits standard fluorescence instrumentation, while the azide handle allows the dye to be incorporated late in probe construction to streamline iterative probe optimization.

3. Nucleic Acid Modification

6-FAM-PEG3-Azide is used in nucleic acid labeling workflows to introduce a fluorescent tag onto oligonucleotides or nucleic-acid-containing assemblies through click conjugation. Researchers developing fluorescent oligo probes, labeled primers, or fluorescently tracked nucleic-acid constructs rely on the azide functionality to attach the dye to alkyne-functionalized strands or nucleic-acid scaffolds. The PEG3 spacer helps reduce dye-backbone proximity effects that can otherwise influence hybridization behavior or accessibility of the labeled construct in fluorescence-based nucleic acid analysis workflows.

4. Surface And Polymer Functionalization

6-FAM-PEG3-Azide is well suited to fluorescent surface engineering and polymer functionalization strategies that employ click chemistry to immobilize a dye at defined density. Materials scientists and biomaterials groups use the azide to couple fluorescent reporters onto alkyne-functionalized surfaces, hydrogels, or polymer backbones, enabling visualization of coating uniformity, material distribution, and surface-associated processes. This approach is particularly useful for constructing fluorescently traceable biomaterial platforms for microscopy studies and for validating functionalization steps during materials development.