Overview of Affinity Agarose Beads

Affinity agarose beads are used in biochemical and molecular biology for purifying proteins, antibodies, and other biomolecules. Made from agarose, these beads are functionalized with specific ligands that bind target molecules with high specificity.

Matrix Composition:

• Agarose: A polysaccharide that forms a porous, stable matrix when cross-linked.
• Pore Size: Controlled by the degree of cross-linking, affecting the separation of biomolecules based on size.

Functionalization Methods:

• Cyanogen Bromide (CNBr) Activation:
  • Rapid and creates stable linkages with primary amines on ligands.
• Epoxy Activation:
  • Versatile, reacts with primary amines, thiols, and hydroxyl groups.
• N-Hydroxysuccinimide (NHS) Ester Activation:
  • High coupling efficiency with primary amines.

Applications:

• Immunoprecipitation (IP):
  • Antibody-coated beads isolate target antigens from mixtures.
• Affinity Chromatography:
  • Ligand-coated beads in columns selectively retain target molecules.
• Protein Purification:
  • Capture tagged recombinant proteins using corresponding ligands.

Key Properties:

• Binding Capacity: Determined by ligand density and target molecule size.
• Stability: Stable across a wide range of pH and ionic strengths.
• Pore Size: Larger pores for large biomolecules, smaller pores for small proteins and peptides.