Patent 7101982 was granted and assigned to Immunex on September, 2006 by the United States Patent and Trademark Office.
The invention provides methods of controlling pH variations during chromatography. In particular embodiments, the invention includes equilibrating and eluting proteins from chromatography resins have a solid phase that possesses a charged functional group on its backbone under controlled conditions of osmolarity and pH. The invention is particularly useful in the purification of proteins that are sensitive to pH transitions such as, for example, the IL-1 Receptor type II protein.