SureLINK Chromophoric Biotin Labeling Kit for Labeling and Quantitation of Biotin in Protein Conjugates

SureLINK Chromophoric Biotin Labeling Kits allow for the easy labeling of proteins with biotin as well as an accurate, precise, and inexpensive method of quantitating biotin in biotin-protein conjugates. Accurate measurement of this parameter is critical for the efficient design of reproducible immunoassays. The basis of the quantitation method is a biotinylation reagent that contains a chromophore in its linker region. Quantitation of biotin by absorbance of the biotin-protein conjugate at 354 nm is superior to the traditional quantitation of biotin using the HABA reagent. We prepared biotinantibody conjugates using the SureLINK Chromophoric Biotin Labeling Kit, and then compared different quantitation methods. Absorbance at 354 nm was more reproducible than HABA-based quantitation, could be performed with lower concentrations of sample, and was nondestructive. The resulting biotin conjugates were used in ELISA, Western blot, and IHC applications.