ABSTRACT
The most often used magnetic beads are produced by Dynal A/S (Oslo, Norway). These “Dynabeads” are superparamagnetic, polystyrenebased particles 2.8 jam (M-280) or 4.5 ]Xm (M-450) in diameter. They are well shaped, spherical beads with iron oxide homogeneously distributed throughout the entire particle. They have a density of 1.5 g/cm3 with an iron content of about 20% (w/v) and a maximum variation in diameter of ± 5% (13). These beads are well suited for high-purity bulk sorting by the separation technique described in this chapter.
