http://www.cd-bioparticles.com/p/Streptavidin-Magnetic-Particles_20_194_237_265.htmlAbsolute Mag Streptavidin Magnetic Particles, 150 nm (# WHM-X050) offer easy affinity isolation or handling of biotinylated nucleic acids, antibodies, or other biotinylated ligands and targets without columns or centrifugation. Our streptavidin magnetic particles are uniform and superparamagnetic beads with a monolayer of recombinant streptavidin covalently coupled to the surface, nearly twice higher binding capacity than typical particles from other suppliers (>4,000 pmol free biotin per mg beads for sizes 50 nm to 200 nm). Unlike many suppliers that block the surface of magnetic particles with BSA or other bio-compatible polymers after the coating of streptavidin, Absolute Mag Streptavidin Magnetic Particles are pre-blocked with biocompatible polymers with significantly low non-specific binding.DNA/RNA Purification, Antibody/Protein Purification