BcMag™ Carboxyl-Terminated Magnetic Beads are uniform, silica-based magnetic beads coated with a high density of carboxylic acid groups on the surface. The hydrophilic surface ensures low nonspecific adsorption, excellent dispersion, and easy handling in various buffers. The high density of pendent functional carboxylic acid groups on their surface allows covalently conjugate primary amine-containing ligands via a stable amide bond. Moreover, the hydrophilic surface ensures beads low nonspecific adsorption, excellent dispersion, and easy handling in various buffers. BcMag™ Carboxyl-Terminated Magnetic Beads are most suitable for conjugating a larger protein. At the same time, BcMagTM Long-arm Carboxyl-terminated Magnetic Beads are recommended for conjugating small peptides because the long-arm hydrophilic linker may reduce steric hindrance.