The present invention relates to a method of purifying albumin-fusion proteins to reduce the level of oxidation of susceptible amino acid residues. The method comprises an affinity matrix chromatography step and an anion exchange chromatography step. The purified albumin-fusion proteins have low levels of oxidation and retain their enhanced half-life in vivo and its bioactivity. In some embodiments, the albumin-fusion protein comprises a scaffold, such as human Tenascin C scaffold. Compositions comprising the albumin-fusion protein are further disclosed.