Fig. 1.

Peptide separations by size exclusion chromatography. UV traces at 215 nm are shown. A, Separation of a model peptide mixture (1 μg per peptide injected) consisting of insulin (1; 5.7 kDa), oxidized insulin A chain (2; 2.5 kDa), and angiotensin II (3; 1.0 kDa). B, Separation of the eight-protein mix cross-linked with DSS and digested with trypsin as the protease (100 μg total protein digest injected). The fractions collected for LC-MS analysis are highlighted. Elution profiles using other proteases are shown in the supplemental Material Fig. S1.