Characterization of Human Serum Albumin isoforms by ion exchange chromatography coupled on-line to native mass spectrometry.

Human Serum Albumin is the most abundant protein of the plasma and displays a wide range of non-oncotic properties such as antioxidant activity, distribution in tissues and organs of binding molecules and clearance of toxic compounds. Albumin is susceptible to numerous post-translational modifications and particularly related to its free thiol group at Cys34 which is the main circulating scavenger of reactive oxygen species. The characterization of these modifications is of high interest for the diagnosis and treatment of patients with liver diseases and for the structural integrity assessment of albumin as a therapeutic protein.