Recombinant Protein Purification & Detection

ANTI-FLAG® M2 Magnetic Beads

The FLAG Expression System is a proven method to express, purify and detect recombinant fusion proteins. Sigma®, the proven provider of FLAG, now offers a magnetic bead for immunoprecipitation, protein purification, and the study of protein-protein interactions.

The ANTI-FLAG M2 Magnetic Bead is composed of murine derived, anti-FLAG M2 monoclonal antibody attached to superparamagnetic iron impregated 4% agarose beads, with an average diameter of 50 µm. The M2 antibody is capable of binding to fusion proteins containing a FLAG peptide sequence at the N-terminus, Met-N-terminus, or C-terminus locations in mammalian, bacterial, and plant extracts.

The magnetic properties allow for:

  • Very rapid separation
  • Significantly accelerated manipulations, such as repetitive washings
  • Processing of multiple samples performed in plate formats

This leads to:

  • Faster experimentation
  • Better reproducibility
  • More accurate quantitation of the proteins of interest



Binding Capacity of the ANTI-FLAG M2 Magnetic Beads

Western blot analysis demonstrates that binding capacity of the ANTI-FLAG magnetic beads when compared to the equivalent agarose conjugate (Product No. A2220).

Courtesy of Drs. Guillaume Adlemant and Jarrod Marto, Blais Proteomics Center, Dana-Farber Cancer Institute.



Purification of Two Different FLAG-tagged Baits

Two different FLAG-tagged baits were purified either from a HeLa-S3 nuclear extract (Nuc. Extr.) or from a HeLa-S3 cytoplasmic fraction (Cyto. Extr.). Both samples were prepared from 10e8 cells. The purifications were performed on the Thermo King Fisher magnetic bead processor. 10% of each FLAG immunoprecepitation elution was loaded on the gel and silver stained.

Courtesy of Drs. Guilaume Adelmant and Jarrod Marto, Blais Proteomics Center, Dana-Farber Cancer Institute.

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