Fluorescent dyes are optimized for labeling proteins, in particular, antibodies. These dyes are bright, photostable and have minimal quenching on proteins. They can be well excited by the major laser lines of fluorescence instruments (e.g., 350, 405, 488, 555 and 633 nm). Streptavidin conjugates are widely used together with a conjugate of biotin for specific detection of a variety of proteins, protein motifs, nucleic acids and other molecules since streptavidin has a very high binding affinity for biotin. A variety of the complementary biotinylated reagents are available from numerous commercial vendors.This Fluorescent 405-streptavidin conjugate comprises streptavidin (as the biotin-binding protein) with Fluorescent 405 covalently attached (as the fluorescent label). It is commonly used as a second step reagent for indirect immunofluorescent staining, when used in conjunction with biotinylated primary antibodies. Fluorescent 405-streptavidin conjugates has fluorescence excitation and emission maxima of ~401 nm and ~420 nm respectively. These spectral characteristics make it an excellent alternative to Alexa Fluor? 405-streptavidin conjugate (Alexa Fluor? is the trademark of Invitrogen). It is a very valuable tool for biotin-streptavidin-based biological assays and tests.
Fluorescent 405-streptavidin conjugate
H303, H313, H333
HeLa cells were incubated with mouse anti-tubulin and biotin goat anti-mouse IgG followed by Fluorescent 405-streptavidin conjugate.
R20, R21, R22
Excitation (nm):403, Emission (nm):427, Extinction coefficient (cm-1 M-1):37000, Quantum yield:0.91