Patent ID: 9695216
Date: 2017-07-04
CPC Classifications: B01D,C07K

Claim:
1. A method comprising: (i) adding allantoin in a supersaturating amount to a protein preparation comprising a desired protein and an amount of at least one endotoxin as a contaminant; (ii) removing solids from the protein preparation to provide a sample for further purification by void exclusion chromatography using a packed particle bed of electropositive particles in a column, the packed particle bed having an interparticle volume; (iii) applying a sample volume of the sample to the packed particle bed, wherein the electropositive particles support void exclusion chromatography, and wherein the sample volume is not greater than the interparticle volume, and (iv) eluting a purified sample comprising the desired protein and a reduced amount of the at least one endotoxin, wherein the eluted desired protein resides in a buffer to which the column was equilibrated, independently from a buffer content of the sample applied to the column.