Ion exchange chromatography column, method, and system thereof

A system for chromatographically separating a sample, the system comprising:

• a pump configured to pump a mobile phase containing the sample from a liquid source;
• an electrolytic eluent generating device fluidically connected to the pump and configured to generate an eluent stream;
• an injection valve configured to inject an aliquot of the sample into the eluent stream;
• a chromatography column fluidically connected to the injection valve and configured to separate one or more analytes from matrix components in the sample, the chromatography column containing a packed bed of a cation exchange chromatographic packing material, the cation exchange chromatographic packing material comprising:
• a) support resin particles;
• and
• b) a copolymer comprising polymerized functional monomers that include a first cation exchange group monomer and a second cation exchange group monomer, where the first cation exchange group monomer and the second cation exchange group monomer are different, in which the copolymer is grafted to the support resin particle,
• in which the first cation exchange group monomer is configured to have a first charge at a first pH, in which the first cation exchange group monomer comprises a sulfonate group at the first pH, and the second cation exchange group monomer is configured to have a net neutral charge at the first pH,
• in which the first cation exchange group monomer is configured to have the first charge at a second pH, and the second cation exchange group monomer is configured to have the net neutral charge at the second pH, in which the first pH and the second pH are different, in which the second cation exchange group monomer is configured to be a zwitterion at the first pH and the second pH,
• in which a mole percent of the second cation exchange group monomer is a mole amount of the second cation exchange group monomer divided by a summation of a mole amount of the first cation exchange group monomer and the mole amount of the second cation exchange group monomer, and multiplied by 100, the mole percent of the second cation exchange group monomer ranges from about 60% to about 99%;
• and
• a detector fluidically connected to an output of the chromatography column.

A method of separating a sample, the method comprising:

• flowing a mobile phase containing a plug of the sample into a chromatography column, the column containing a packed bed of a cation exchange chromatographic packing material, the cation exchange chromatographic packing material comprising:
• a) support resin particles;
• and
• b) a copolymer comprising polymerized functional monomers that include a first cation exchange group monomer and a second cation exchange group monomer, where the first cation exchange group monomer and the second cation exchange group monomer are different, in which the copolymer is grafted to the support resin particle,
• in which the first cation exchange group monomer is configured to have a first charge at a first pH, in which the first cation exchange group monomer comprises a sulfonate group at the first pH, and the second cation exchange group monomer is configured to have a net neutral charge at the first pH,
• in which the first cation exchange group monomer is configured to have the first charge at a second pH, and the second cation exchange group monomer is configured to have the net neutral charge at the second pH, in which the first pH and the second pH are different, in which the second cation exchange group monomer is configured to be a zwitterion at the first pH and the second pH,
• in which a mole percent of the second cation exchange group monomer is a mole amount of the second cation exchange group monomer divided by a summation of a mole amount of the first cation exchange group monomer and the mole amount of the second cation exchange group monomer, and multiplied by 100, the mole percent of the second cation exchange group monomer ranges from about 60% to about 99%;
• and
• separating the sample into one or more analyte bands in the chromatography column;
• and
• detecting the one or more analyte bands eluting off the chromatography column.

A cation exchange chromatographic packing material comprising:

• a) support resin particles;
• and
• b) a copolymer comprising a first cation exchange group, a second cation exchange group, and a third cation exchange group where the first cation exchange group and the second cation exchange group are different, in which the copolymer is grafted to the support resin particle,
• in which the first cation exchange group is configured to have a first charge at a first pH, in which the first cation exchange group comprises a sulfonate group at the first pH, and the second cation exchange group is configured to have a net neutral charge at the first pH,
• in which the first cation exchange group is configured to have the first charge at a second pH, and the second cation exchange group is configured to have the net neutral charge at the second pH, in which the first pH and the second pH are different, in which the second cation exchange group is configured to be a zwitterion at the first pH and the second pH,
• where the third cation exchange group is different from the first cation exchange group and the second cation exchange group, in which the third cation exchange group is configured to have a second charge at both the first pH and the second pH, where the second charge and the first charge both have the same polarity.