http://www.cd-bioparticles.com/p/Carboxyl-Magnetic-Particles_20_193_211_296.htmlAbsolute Mag™ Carboxyl Magnetic Particles, 0.4-0.69 μm (# WHM-S026) contain carboxylic acid groups which can be used for carbodiimide activation (e.g. EDC) for covalent coupling, prepared by coating a layer of magnetite and polystyrene onto monodispersed polystyrene core particles. These magnetic particles are useful during the isolation and affinity purification of biomolecules in a wide range of assays and applications, such as cell separation, affinity purification, DNA probe assays, magnetic particle EIA, etc.Antibody/Protein Purification