BeaverBeads Protein A/G Antibody Purification Kit

Product Overview

The BeaverBeads™ Protein A/G Antibody Purification Kit purifies immunoglobulin in a single magnetic step. The beads are 2 µm superparamagnetic microspheres, NHS-activated and then covalently bound to recombinant Protein A/G, supplied at 30 mg/mL with a complete set of pre-formulated binding, elution, neutralisation, washing, storage and regeneration buffers.

Covalent attachment through NHS chemistry is what keeps ligand leaching low: the manufacturer states that residual Protein A in the purified antibody stays below the US FDA reference limit of 20 ppm. Antibody purity from a serum sample is reported at over 90% after one purification.

Speed and capacity

Human IgG binding capacity: 1.8–2.0 mg per mL of Protein A/G beads (the Protein A version, Cat. 20102, is quoted at 1.4–1.6 mg/mL). A skilled operator completes antibody adsorption in 15 minutes and the whole purification in 30 minutes.

Reusable, with a defined regeneration protocol

The kit includes a dedicated regeneration buffer. BEAVER recommends regenerating after five continuous uses: 5 mL of regeneration buffer per 1 mL of 10% (v/v) beads, mixed 10 minutes at room temperature, then two washes in binding/washing buffer and resuspension in storage buffer. The published durability data are 75% of original IgG binding capacity retained after 15 cycles, recovering to 90% after regeneration treatment, and no measurable loss of antibody binding after 8 weeks at 37 °C.

Two elution routes

Elution Buffer I at pH 4.5 is the gentler option and the manufacturer's default. Elution Buffer II at pH 2.0 is there for antibodies that bind too tightly to release at pH 4.5. Both are followed immediately by the neutralisation buffer. If elution is still incomplete, the manual suggests lowering the pH into the 1.9–2.5 range, raising ionic strength with 2–3 M MgCl₂, or extending the elution time — while warning that antibodies aggregate readily at low pH, so neutralise promptly.

Sample types

Serum, blood plasma, ascites, cell lysate and tissue culture supernatant. The kit is also used for antibody immobilisation studies. A species and isotype affinity table in the manual lets you choose between the Protein A and Protein A/G versions for your antibody.

Handling and safety

A magnetic separator is required. Vibrate the beads thoroughly before use and keep them in storage solution so they never dry out. Do not freeze or centrifuge the beads — both cause irreversible aggregation. 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 and protocol are those published by the manufacturer, BEAVER Biomedical Engineering Co., Ltd.