Analysis of L19 IgG-GyrA integrity after EPL. (A) Non-reducing (ox) and reducing (red) SDS-PAGE (Coomassie stained). (B) Analytical Gel Filtration. Black: L19 IgG-GyrA before cleavage. Dotted: Purified EPL product. Grey: L19 IgG control antibody. (C) SPR analysis. Results were fitted to a one-site-binding model with a KD of 91.4 nM.