Solid-phase extraction with the weak cation-exchange resin Fractogel TSK CM650(S) (TSK CM) was used to optimize the sensitivity and chromatographic resolution by HPLC of the mutagenic heterocyclic aromatic amines MeIQx, 4,8-DiMeIQx, IQ, MeIQ, PhIP, Trp-P-1, Trp-P-2, amino-alpha-carboline and the co-mutagens norharman and harman. The clean-up using cation exchange was applied after purification on Extrelut and propylsulphonic acid-silica gel cartridges (PRS tandem purification). Only the clean-up with TSK CM enabled low detection limits of the mutagenic compounds to be achieved (in the order of ng heterocyclic amines/g experimentally overheated process-flavour sample).