aPlasma IgG solution (11 mg/mL) with no aggregate spike
bAggregate-spiked plasma IgG solution (11 mg/mL); plasma IgG spiked at 0.5% with IgG aggregate (14.8% dimer and 57.1% trimer or larger species) prepared for application to column chromatography and adjusted to 11 mg/mL for analysis and virus filtration