Phoenix Pharmaceuticals has successfully applied antibodies onto magnetic particles. Magnetic particles are a convenient affinity support for a variety of assays, which allow easy purification of the target without columns or centrifugation. PhoenixParticles are available pre-coated with Protein A, Protein G, streptavidin, anti-mouse or anti-rabbit antibodies.

Highlights:

·         Analysis of plasma or small body fluid samples for MODI-TOF MS. This magnetic-bead-based platform amenable to high-throughput peptide capture and demonstrated that antibody capture followed by mass spectrometry can achieve ion signal enhancements on the order of 10³, with precision (CVs <10%) and accuracy.

·         Particles respond well to magnetic fields but have no magnetic memory.

·         Most separations require a short 2- to 10-minute bench-top procedure.

·         Bead specifications – surface area: >100 m²/g, 1-2 µm or 0.6 –1 µm diameter depending on application.

·         PhoenixParticles are available pre-coated with Streptavidin, Protein A or G, antibodies and can be used for either positive or negative selection .

·         Cell can be isolated by binding directly to primary antibody or PhoenixParticles.

·         Cell type isolated by PhoenixParticles is determined by the primary antibody bound indirectly to the secondary antibody coated bead.

·         Quick and simple method for peptide/protein purification or removal of  un-needed proteins/peptides.

References:

1.       Schneider, C., Newman, R.A. et al. (1982). J. Biol. Chem. 257, 10766.

2.       Sisson, T.H. and Castor, C.W. (1990). Immunol. Methods. 127, 215.

3.       Hortin, G. L. (2006). Clin. Chemistry 52, 1223-1237.

4.       Neaey, S.E., et al. (2001). J. Biol. Chem. 276(9), 6645-6655.

5.       Chaudhuri, T.K., et al. (2001). Cell 107, 235-246.

6.       Whiteaker J.R.  et al. (2007)  Ana. Biochem. (article in press).