| Description | Casein is considered to be a generic substrate for a broad spectrum of proteases. As native casein this fluoresceinated casein is hydrolyzed by many proteases, and widely used for fluorimetric measurement of protease activity. In the intact substrate, casein is heavily labeled with 5-FITC, resultingCasein is considered to be a generic substrate for a broad spectrum of proteases. As native casein this fluoresceinated casein is hydrolyzed by many proteases, and widely used for fluorimetric measurement of protease activity. In the intact substrate, casein is heavily labeled with 5-FITC, resulting in significant fluorescence quenching. Protease-catalyzed hydrolysis relieves its quenching effect, yielding brightly green fluorescent dye-labeled short peptides. The increase in fluorescence intensity is directly proportional to protease activity. We do not recommend that this conjugate be used for fluorescence polarization assay. For fluorescence polarization we can custom-make the lightly labeled fluorescein casein conjugate... Read More | Inquire | Usually used industrially for the resolution of chiral compounds and the transesterification production of biodiesel | N-Acetylneuraminyl-fucosyllacto-N-neo-tetraose is used as a reference material in the analysis of milk oligosaccharides | BackgroundStreptavidin is a tetrameric bacterial protein isolated from Streptomyces avidinii providing 4 high-affinity biotin binding sites. Streptavidin homo-tetramers have an extraordinarily high affinity for biotin. With a dissociation constant on the order of ≈10⁻¹⁴ mol/L,BackgroundStreptavidin is a tetrameric bacterial protein isolated from Streptomyces avidinii providing 4 high-affinity biotin binding sites. Streptavidin homo-tetramers have an extraordinarily high affinity for biotin. With a dissociation constant on the order of ≈10⁻¹⁴ mol/L, the binding of biotin to streptavidin is one of the strongest non-covalent interactions known in nature. Unlike egg-white avidin, which has a net positive charge at neutral pH and contains about 7% carbohydrate, streptavidin has almost no net charge at neutral pH, does not contain carbohydrate, and exhibits lower non-specific background. 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. This FITC-streptavidin conjugate was prepared by highly purified Streptavidin and free FITC was removed. Streptavidin (FITC) is a useful second-step reagent for the indirect immunofluorescent staining of cells in combination with biotinylated primary antibodies for flow cytometric analysis. Excitation at 488nm light leads to a fluorescence emission maximum of 520 nm.Recommended Usage：Every lot of Streptavidin-FITC is tested by flow cytometry using biotinylated primary antibodies. From this testing it is recommended that between 0.02 and 0.25 µg of streptavidin be used per 106 cells in a 100 µl staining volume... Read More |