Absolute Mag™ Hydroxyl Magnetic Particles, PVA, 0.5-1 μm (# WHM-C309) consist of a matrix of polyvinyl alcohol, which is suitable for a variety of applications e.g. for the binding of proteins to the available hydroxy functionalities with known coupling methods (e.g. activation with tosyl chloride or epichlorhydrine). Their high magnetite content permits a rapid separation process. The beads have a polydisperse size distribution.