Figure 2: CZE separations of rituximab using running buffer of different pH. Conditions: 400 mM EACA, 2 mM TETA, 0.05% HPMC, capillary: 64.5 cm x 50 μm i.d., leff: 8.5 cm, samples were injected by 150 mbar.s at the anodic end of the capillary, closer to the detection window ("short end injection"), -15 kV, λ= 200 nm. The 10 mg/ml pharmaceutical product MabThera was tenfold diluted with water.