(EN) A flow-through chromatography method of separating a monomeric protein of interest from protein aggregates in a sample, the method comprising contacting the sample with a solid support comprising a polymer attached thereto, wherein the polymer comprises one or more cation exchange binding groups and one or more dimethylacrylamide groups, wherein the dimethylacrylamide groups are present in a greater number than the one or more cation exchange binding groups, thereby separating the monomeric protein of interest from the protein aggregates.