Protein was dialyzed against the same buffer for 16-18 h with a buffer exchange after 12 h of dialysis at 4 °C. The dialyzed protein was then subjected to anion exchange chromatography (AEC) (HiTrap Q Hp 5 ml, GE healthcare) followed by size exclusion chromatography (SEC) (HiLoad 16/600 Superdex 200 pg. column). Monomeric fraction of αSyn eluted in 10 mM of sodium phosphate buffer (pH 7.4) was collected, and protein concentration determined by UV-absorption at 280 with theoretical molar extinction coefficients calculated from the protein sequence using ProtParam80 (Expasy, Switzerland).