Patent ID: 8394921
Filing Date: 2013-03-12
Classification: A61K,A61P,C07K,C12N,C12Y,Y02A

Abstract:
1. A method for producing a composition comprising a population of polysialic acid derivatives of a protein, wherein the derivatives comprise between 2 and 200 sialic acid units and wherein the population consists substantially only of N-terminal derivatives of the protein, said method comprising: (i) reacting a polysialic acid at the amine group of the N-terminus of a protein in aqueous acidic solution to produce an N-terminal derivative; and (ii) purifying the resultant N-terminal derivative in aqueous solution of higher pH than in (i); wherein the pH of the aqueous solution in (i) is in the range 4.0-6.0 and in step (ii) is in the range 6.5-8.5.