Complex sentence: The agarose beads used are typically of 4% and 6% densities, and are highly porous, so allowing protein to flow freely through the beads and bind to the ligands, so they have a high binding capacity for protein.
Split into simpler sentences: The agarose beads used are typically of 4% and 6% densities, and are highly porous. They allow protein to flow freely through the beads and bind to the ligands, so they can have a high binding capacity for protein.