Cleavable Aldehyde-Activated Magnetic Beads for Efficient Immobilization

BcMag™ Cleavable Aldehyde-Activated Magnetic Beads are uniform, silica-based superparamagnetic beads grafted with a high density of cleavable aldehyde functional groups on the surface. The bead aldehyde groups react spontaneously with primary amines present at the N-terminus of proteins or in lysine residues to form intermediate Schiff Base complexes. The reaction of reductive amination immobilization starts with the creation of an initial Schiff base between the aldehyde and amine groups, which is then reduced to a secondary amine by the addition of sodium cyanoborohydride (NaCNBH₃) to generate stable amine bonds between the Bead and the ligand. At physiological to alkaline circumstances (pH 7.2 to 9) in either aqueous or organic solvents with 20- 30% DMSO or DMF, coupling reaction takes 2 to 6 hours in a one-step process. Coupling efficiency with antibodies and normal proteins is usually better than 85%, resulting in 15 – 20 µg /mg of beads.