Patent ID: 8679346

Claim:
A method of producing an enantiomeric isomer separating agent comprising a polysaccharide derivative supported on particles of a support by chemical bonding and having a concentration of eluted component, in terms of mass proportion, of no more than 20 ppm, said method comprising the steps of: washing an enantiomeric isomer separating agent comprising the polysaccharide derivative supported on particles of a support by chemical bonding and having a concentration of eluted component, in terms of mass proportion, of greater than 20 ppm, at least once with an organic solvent in which the polysaccharide derivative is soluble, the organic solvent being at a temperature of from 50-150° C. and selected from the group consisting of tetrahydrofuran, acetone, ethyl acetate, methylene chloride, dimethylacetamide and dimethylformamide for a period of from 1-100 hours and drying the washed enantiomeric isomer separating agent, wherein the concentration of eluted component is determined by a liquid passing test comprising the steps of: packing the enantiomeric isomer separating agent in a column having a diameter of 1 cm and a length of 25 cm by a slurry method; passing the organic solvent in which the polysaccharide derivative is soluble in and at a temperature of 40° C. through the enantiomeric isomer separating agent in the column at a flow rate of 8 ml/min and forming an eluate; initiating the collection of the eluate one hour after initiating the passing of the solvent through the enantiomeric isomer separating agent in the column and measuring the mass, M 1 , of the eluate collected; condensing and drying the collected eluate and measuring the mass, M 2 , of remaining residue; and determining the concentration of the eluent component from the expression M 2 /M 1 .