WangLab:Covalently Coupling Beads FN EGF

Protocol for the coupling beads with Fn or EGF:

 * 1) Carboxy-functionalized super-paraagnetic beads (1 m, SERA-MAG, #294766050250) were activated with 0.1M sulfo-NHS, 0.1M EDC in 0.1M MES (ph 5.0) for 1 hr at RT.
 * 2) 2X wash 0.1M MES,
 * 3) Equilibrate with coupling buffer (0.1M sodium phosphate, ph 8.0)
 * 4) Coupling at 4oC overnight (
 * 5) Rinse thoroughly with PBS