An assortment of reagents for the purification of biotin labelled proteins are available from G-Biosciences. For single step, small and large scale affinity purifications try Immobilized Avidin Resin. With similar binding to biotin as avidin but less non-specific binding we offer Immobilized Streptavidin Resin. The advantage of streptavidin is that the lack of carbohydrates significantly reduces the amount of non-specific binding. Immobilized Streptavidin Resin is available as slurry or in a 1mL spin-column format. G-Biosciences Immobilized Monomeric Avidin Resin is designed for the simple affinity chromatography purifications of proteins, antibodies and other molecules with a biotin tag. The resin consists of monomeric subunits of avidin covalently coupled to 6% cross-linked agarose, offering a stable, reusable resin for the purification of biotinylated molecules. Monomeric avidin offers a distinct advantage over native avidin, a tetrameric molecule, and streptavidin as it has a much lower biotin binding affinity, Kd=10-7 as opposed to Kd=10-15 for native avidin.This lower binding affinity allows elution of molecules with mild elution buffers (2mM D-Biotin in 1X PBS), as opposed to the strong denaturing buffers (8M Guanidine•HCl, pH 1.5) used with native avidin.
Accurate estimation of the molar ratio of biotin conjugated to protein/antibody is easy and affordable with HOOK™ BiotinQuant™ Kit. HOOK™ Cell Surface Protein Isolation Kit uses G-Biosciences HOOK™ biotin labeling and purification technology in conjunction with our Mammalian Cell PE LB™ lysis buffer to conveniently label cell surface proteins and isolate them for further analysis, including Western blotting.