Luminex Bead Coupling
Vortex the bead stock suspension to yield a homogeneous bead suspension.
Dissolve approximately 10 mg each of EDC and S-NHS into 2 microcentrifuge tubes and resuspend in deionized water at 50 mg/mL.
Centrifuge the 100 μl bead suspension at 10,000 x g. 
Carefully remove and discard the supernatant.
Resuspend the beads in 80 μl activation buffer.
Add 10 μl of S-NHS solution and 10 μl of EDC solution to the bead suspension.
Incubate with agitation at room temperature in the dark at roughly 900 rpm.
Dilute your protein stock solution with coupling buffer to a concentration of 0.1 mg/ml in a volume of 100 μl.
Optimal coupling may occur at a concentration within 25-250 μg/ml.
Note the protein stock cannot have any other amine groups present.
Centrifuge the beads at 10,000 x g. 
Carefully remove and discard the supernatant.
Add the diluted protein solution.
Agitate the tube with activated beads and protein solution overnight at 4C at roughly 900 rpm in the dark (wrapped in foil).
Centrifuge the beads at 10,000 x g. 
Discard supernatant.
Wash the beads three times with PBS/1% BSA.
Resuspend the bead pellet in 1 ml PBS/1% BSA.
Determine bead concentration using Luminex and adjust amount of stock used accordingly.
