Affinity matrix with immobilized Protein-A (from staphylococcus aureus) by CNBr activation coupling method. For purification and/or fractionation of IgG subclasses. Reliable tool to purify monoclonal and polyclonal IgG from ascies, serum and cell culture supernatants.
Provided as pre-packed, ready-to-use Protein A Separopore® Chromatography Cartridges. Conveniently packed in a 2.5 ml in-line column capable of running at low pressures. Fittings to attach with any HPLC or FPLC systems are provided separately.
- Ligand: Native protein A from Staphylococcus aureus.
- Ligand coupling method: CNBr activation.
- Binding capacity: approximately 20mg human IgG/ml drained gel.
- Matrix: Cross-linked agarose beads, 4%.
- Exclusion limit: approximately 2 x 107.
- Particle size (range): 45-165µm.
- pH stability: 3-9 (for use), 2-10 (for cleaning).
- Supplied as suspension (50% slurry) in 0.5M NaCl.
- Storage: 2-8ºC.
IP with Protein A
- Add 3 ml ice cold RIPA buffer to cell monolayer (or approximately 2–5 x 107 suspension cells in flask) and incubate at 4° C for 10 minutes. For suspension cells, add the RIPA buffer to washed cell pellet in a 15 ml conical centrifuge tube.
- Disrupt cells by repeated aspiration through a 21 gauge needle and transfer to a 15 ml conical centrifuge tube.
- Wash cell culture plate with additional 1.0 ml ice cold RIPA buffer and combine with original extract.
- Pellet cellular debris by centrifugation at 10,000xg for 10 minutes at 4° C. Transfer supernatant to a 15 ml conical centrifuge tube kept on ice. Preclear lysate (optional step) by adding 1.0 µg of the appropriate control IgG (normal mouse, rat, rabbit or goat IgG, corresponding to the host species of the primary antibody)towns add 20 µl of resuspended volume of Protein A-Separopore. Incubate at 4° C for 30 minutes.
- Pellet beads by centrifugation at 2,500 rpm (approximately 1,000xg) for 5 minutes at 4° C. Transfer supernatant to a fresh 15 ml conical centrifuge tube kept on ice.
- Transfer 1 ml of the above cell lysate, or approximately 100–500 µg total cellular protein, to a 1.5 ml microcentrifuge tube. Add 1–10 µl (i.e., 0.2–2 µg) primary antibody (optimal antibody concentration should be determined by titration) and incubate for 1 hour at 4° C. longer incubation. May be. Required for some low titter antibodies.
- Add 20 µl of resuspended volume of Protein A-Separopore. Cap tubes and incubate at 4° C on a rocker platform or rotating device for 1 hour.
- Collect immunoprecipitates by centrifugation at 2,500 rpm (approximately 1,000xg) for 5 minutes at 4° C. Carefully aspirate and discard supernatant.
- Wash pellet 4 times with 1.0 ml RIPA buffer (more stringent) or PBS (less stringent), each time repeating centrifugation step above.
- After final wash, aspirate and discard supernatant and resuspend pellet in 40 µl of 1x electrophoresis sample buffer.
- Boil samples for 2minutes and analyze 20 µl aliquots by SDS-PAGE and follow it by Western blot analysis or auto radiography if sample was labeled.
Usage : bioWORLD's products are supplied for LABORATORY RESEARCH USE ONLY. The product may not be used as a drug, agricultural or pesticidal product , food additive or as a household chemical.