Affinity chromatography separates proteins on the basis of a reversible interaction between a protein and a specific ligand covalently bound to a pre-activated chromatographic medium. The typical affinity chromatography is often referred to as ”lock and key principle“ of a part of a molecule (key) with an immobilized ligand (lock). Antibodies, antigens, enzymes, short nucleic acids, peptides or chemical entities can be used as affinity ligands. They are coupled via their reactive functional groups such as amino, carboxyl, hydroxyl of thiol moieties to the resin. In affinity chromatography, non-binding molecules are almost entirely eliminated through wash buffers and the final elution typically contains the target molecule at a high level of purity. One common example of affinity purification, is the use of antigens or antibodies as ligands to create a highly selective resin for imunoaffinity purification of antibodies, proteins or other molecules.

BioFox™ ACT resins are produced from agarose beads using a proprietary cross-linking method that results in a highly porous and physically stable agarose matrix. These resins are stable at pressures up to 580 psi allowing for high throughput and resolution biochromatography. BioFox™ 40 ACT is activated according to the bromhydrin method. This activa¬tion method is based upon well characterized chemistry that permit coupling reactions in an aqueous solutions at room temperature.

Coupling conditions and selection of coupling buffers
BioFox 40 ACT comes ready to use. Proteins or other biomolecules with free amino and thiol groups will easily couple to BioFox 40 ACT. Just add the ligand to the suspension, stir and incubate overnight. Thiol groups are coupled in buffer at pH 7 and higher and amino groups at pH 8 to 8.5 The low nucleophilicity of the hydroxyl group required coupling at pH 12. This is not compatible with most proteins, however, molecules stable at this pH can be coupled using the hydroxyl group or a larger molar excess of ligand can be employed to compete against the hydrolysis reaction that occurs at lower pH’s. Remaining reactive groups on the resin are deactivated using 2-mercaptoethanol or ethanolamine.

BioFox™ 40 ACT resin is stable for 12 months in aqueous solutions containing 22 % ethanol at neutral pH and at room temperature without any significant decrease of coupling activity. The choice of storage buffer for a coupled gel medium depends on the properties of the ligand. The resin is stable in 100% methanol, 100% ethanol, 8 M urea, 6 M guanidine-HCl, 70% formic acid and 30% trifluoracetic acid. The degree of stability of a given ligand couple to 40 ACT resin depends on the physical-chemical properties of the ligand.

• Resin Sizes: 32-60 µm
• Max. Flow Rate (at 20cm height): 500 ml/min
• Degree of Substitution: 0.6-0.7 mol/mol
• Spacer Arm: 4-16 atoms
• Exclusion Limit: 1,200 kDa

• Resin Sizes: 32-60 µm
• Max. Flow Rate (at 20cm height): 500 ml/min
• Degree of Substitution: 0.6-0.7 mol/mol
• Spacer Arm: 4-16 atoms
• Exclusion Limit: 1,200 kDa