Protein A/G Magnetic Beads

Product Discontinued

Applications/Dilutions

• Dilutions:
  • Chromatin Immunoprecipitation
  • Immunoprecipitation
  • Western Blot
• Application Notes: Protein AG Magnetic Beads are useful for Immunoprecipitation for analysis in non-reducing conditions as well as Antibody Purification. Sufficient For: Binding 55 to 85 ug rabbit IgG/mg beads. Also useful in Chromatin Immunoprecipitation. Beads are 1um in diameter.

Packaging, Storage & Formulations

• Storage: Store at 4C. Do not freeze.
• Buffer: supplied at 10mg/mL in water containing 0.05% NaN3
• Concentration: Please see the protocols for proper use of this product. If no protocol is available, contact technical services for assistance.

Notes

Important Product Information: Do not centrifuge, allow beads to dry or freeze. Centrifuging, drying or freezing will cause the beads to aggregate and lose binding activity. Always vortex beads to fully resuspend before pipetting. To minimize protein degradation, include protease inhibitors in preparation of cell lysates. - A low-pH elution may be used for single-use applications. Optimal time for low-pH elution is 10 minutes; exceeding 10 minutes may result in nonspecific binding and yield reduction. - When using rabbit antibodies (primary or secondary) in downstream Western blot applications, perform elution in SDS-PAGE sample buffer at room temperature. For all other antibody species, boiling the beads in SDS-PAGE sample buffer is acceptable for single-use applications. Boiling could cause bead aggregation and loss of binding activity. Protein A/G Magnetic Beads are compatible with small-scale antibody purification and immunoprecipitation and analyses by Western blot and mass spectrometry. Protein A/G has a broader binding range than either Protein A or Protein G individually. Protein A/G binds to all human IgG subclasses, binds somewhat to IgA, IgE, IgM and, to a lesser extent, IgD. Unlike Protein G, Protein A/G does not bind serum albumin because the gene sequence coding for the albumin-binding site has been eliminated. Protein A/G is effective for mouse monoclonal antibody purification from IgG subclasses because Protein A/G binds all mouse IgG subclasses but does not bind murine IgA, IgM or serum albumin.

Background

The recombinant Protein A/G that is immobilized onto the Magnetic Beads is a fusion of the IgG binding domains of both Protein A and Protein G. Protein A/G contains four Fc-binding domains from Protein A and two from Protein G, making it a convenient tool for investigating and purifying immunoglobulins. Thus, Magnetic Particles are not simply a mixed immobilization of separate Protein A and Protein G polypeptides, nor are they a mixture of Protein A magnetic beads and Protein G magnetic beads.

Limitations

This product is for research use only and is not approved for use in humans or in clinical diagnosis. Support products are guaranteed for 6 months from date of receipt.

Publications for Protein A/G Magnetic Beads (NBP1-71715)(1)

Publication using NBP1-71715

• Ziyatdinova S, Viswanathan J, Hiltunen M, Tanila H. Reduction of Epileptiform Activity by Valproic Acid in a Mouse Model of Alzheimer's Disease is not Long-lasting after Treatment Discontinuation Epilepsy Res 2015-04-08 [PMID: 25847338]

FAQs for Protein A/G Magnetic Beads (NBP1-71715). (Showing 1 - 4 of 4 FAQ).

1. I have one question about ChIP. In your Chromata ChIP kit, you add 25ul magnetic beads to the samples. Is there any way to normalize for differences in the amounts of magnetic beads in each sample? For example, it can happen that one sample got a bit more beads than another, is there some way to take this into account when you analyze your data?
   • As long as the vial/bottle of beads is vortexed so that the beads are fully resuspended in solution before taking the 25ul out, there will not be any significant variation in bead number. However, if you are taking multiple 25ul aliquots out, it is best to quickly revortex before every aliquot pipetting. For all of our internal testing, we typically see a CV of less than 2% for both intra- and interassay variation, which is very good.
2. I am running an immunoprecipitation experiment with vWF and was wondering if Novus sells agarose beads in which I could conjugate the anti-Von Willebrand factor to the beads?
   • For immunoprecipitation, agarose or magnetic beads coupled to Protein A, Protein G or Protein A/G are used. These three proteins all bind to antibodies, although with binding affinities that vary depend on the host species / isotype of the antibody. The only agarose bead type we sell here at Novus is Protein A Agarose (catalog number 851-0024). This particular product is made by a company called Innova Biosciences; we are their distributor in this case. They have designed this product for antibody purification, but it should also be suitable for IP, and we have received a customer review that it works well in IP. To see how well this Protein A Agarose binds to antibodies of different species/isotypes, I suggest you consult the table in the protocol. Innova Biosciences also make the equivalent Protein G Agarose, although we don't currently stock it here at Novus. Protein G is better for certain antibody host species; please see the table in the protocol for this product. Here at Novus, we have an alternative to the traditional agarose beads coupled to Protein A or G, and that is magnetic beads conjugated to Protein A/G: catalog number NBP1-71715. Protein A/G is a recombinant fusion protein that combines the IgG binding domains of both Protein A and Protein G, and hence enables capture of antibodies from a wider range of species and isotypes than either protein alone. Moreover, here is a brief article on the advantages of using magnetic beads rather than agarose beads.
3. I have a question regarding the following product: NBP1-71715. What is the size (diameter) of the magnetic beads? And is it possible to use these beads in connection with an antibody to select /isolate cells?
   • These beads are 1um in diameter. They are protein A/G beads, so they will bind to the antibody and can be used to select for cells.
4. What is the exp. date for NBP1-71715, Lot no. PF 1852351 ?
   • These Protein A/G Magnetic beads do not have an expiry date. As stated on our web page we have a 6 months warranty for supporting this product from date of purchase if stored as recommended at 4 degrees C.