Patent ID: 8524864
Filing Date: 2013-09-03
Classification: A61K

Abstract:
1. A method for producing a conjugate of thyroxine and albumin which comprises: step (a) of converting a carboxyl group in thyroxine having a carboxyl group to be linked to albumin into an active ester and allowing the thyroxine to react with albumin, so as to prepare a conjugate of thyroxine and albumin; and step (b) of purifying the conjugate with the use of an acidic mixed aqueous solvent in which the thyroxine having a carboxyl group to be linked to albumin is dissolved but albumin is not precipitated, wherein the thyroxine having a carboxyl group to be linked to albumin is represented by the following formula (1): wherein X represents a lower alkyl group, and L represents a linker; and the acidic mixed aqueous solvent is composed of water, an acid and an organic solvent where the acid is selected from the group consisting of trifluoroacetic acid, hydrochloric acid, sulfuric acid, acetic acid and trichloroacetic acid, and the organic solvent is selected from the group consisting of acetonitrile, N,N-dimethylformamide, dimethyl sulfoxide and methanol.