BeaverBeads Magrose Heparin Affinity & Cation Exchange Magnetic Beads

Product Overview

BeaverBeads™ Magrose Heparin are superparamagnetic agarose microspheres carrying immobilised heparin. Heparin is unusual among purification ligands because it works two ways at once: it is a specific biological affinity ligand for growth factors, antithrombin III and a range of nucleic acid-binding proteins, and — because of its dense negatively charged sulfate groups — it is also a strong cation exchange medium for positively charged proteins at a given pH. One resin, two separation mechanisms.

The magnetic format removes the column. Crude protein samples do not need the repeated centrifugation and time-consuming filtration that column chromatography demands, there is no flow rate or column pressure to manage, and no chromatography instrument is required. The manufacturer reports that a skilled operator can extract high-purity protein in a very short time and run many samples in parallel.

Capacity and conditions

Ligand density is approximately 3 mg of heparin per mL of gel. Protein binding capacity is quoted as approximately 2 mg of antithrombin III per mL of beads — a reference figure, since real capacity depends on the target protein. Note that the product is a 10% (v/v) suspension, so 1 mL of what you pipette contains 100 µL of beads.

The manufacturer's starting conditions are a binding buffer of 50 mM Tris-HCl at pH 8.0 and an elution buffer of 50 mM Tris-HCl with 1–2 M NaCl at pH 8.0. Salt concentration and pH both change which proteins bind and how they release, so screen these for your target before scaling up.

Applications

Purification of antithrombin III and other coagulation factors, thrombin, growth factors, interferons, steroid receptors, lipoproteins, nucleic acid-binding proteins and restriction endonucleases. Also used as a general cation exchange capture step where a heparin-mimetic selectivity is wanted.

Handling and safety

Do not freeze, dry out or centrifuge the beads — all three cause aggregation that is hard to resuspend and damages the surface chemistry. Vortex or sonicate to an even suspension before every use. If the ethanol preservative interferes with your chemistry, wash the beads two or three times with purified water or buffer first. A magnetic separator is required. Keep beads and separators away from metal objects, electronic devices and implanted electronic devices such as cardiac pacemakers.

For Research Use Only. Not for use in diagnostic or therapeutic procedures. Specifications are those published by the manufacturer, BEAVER Biomedical Engineering Co., Ltd.