Patent ID: 6489447
Filing Date: 2002-12-03
Classification: A61K,A61P,C07K

Abstract:
A method for purifying a polypeptide from a composition comprising the polypeptide and a deamidated variant thereof, which method comprises the following steps performed sequentially:(a) binding the polypeptide and deamidated variant to an ion exchange material using a loading buffer, wherein the loading buffer is at a first conductivity and pH; (b) washing the ion exchange material with an intermediate buffer at a second conductivity and/or pH so as to elute the deamidated variant from the ion exchange material; (c) washing the ion exchange material with a wash buffer which is at a third conductivity and/or pH, wherein the change in conductivity and/or pH from the intermediate buffer to the wash buffer is in an opposite direction to the change in conductivity and/or pH from the loading buffer to the intersediate buffer; and (d) washing the ion exchange material with an elution buffer at a fourth conductivity and/or pH so as to elute the polypeptide from the ion exchange material.