Hydrophobic Interaction Chromatography
The overall hydrophobicity of the BsAbs was assessed by hydrophobic interaction chromatography (HIC-HPLC). Samples were diluted to 1mg/ml in PBS and injected onto a TSKgel Butyl-NPR HIC column (Tosoh Cat.# 0014947) preequilibrated in 25mM potassium phosphate, 1.5M ammonium sulfate, pH 6.8. Samples were eluted with a 20-minute linear gradient into 25mM potassium phosphate, pH 6.8, 20% isopropanol.