Add 180 µL of 50% suspension of ion exchange beads to each well of a 96-well Silent Screen filter plate and drain off the W1 bead-washing buffer by vacuum.
Wash the ion exchange beads in each well three more times by adding 200 µL of Q1 bead equilibration buffer to the beads and draining off the buffer by vacuum.
After the last vacuum drain, transfer 50 µL of the denatured serum sample from the well in the sample plate to the corresponding well in the filter plate containing the equilibrated ion exchange beads.
Add 50 µL of Q1 buffer to the well in the sample plate where serum was originally placed and rinse the residual serum by pipetting up and down five times.
Transfer the 50 µL of the serum rinse to the well in the filter plate containing the mixture of denatured serum sample and ion exchange beads.
Shake the filter plate vigorously on the Micromix shaker (in an amplitude of 7 and form of 20 Hg) for 30 min at 4°C to mix the serum and beads well.