摘要 |
<p>The invention relates to the purification of different gamma carboxylated forms of a polypeptide using ion exchange chromatography. In particular, the invention provides a method for purifying a polypeptide having a desired content of gamma-carboxyglutamic acid from a sample comprising mixture of species of said polypeptide having different contents of gamma-carboxyglutamic acid, said method comprising the steps of: (a) loading said sample onto an anion exchange chromatography material; (b) eluting said polypeptide using a solution at a pH of less than pH 9.0 comprising at least one salt selected from ammonium acetate, ammonium chloride and sodium acetate; and (c) selecting a fraction obtained from said elution wherein the polypeptides in the fraction have the desired content of gamma-carboxyglutamic acids.</p> |