Analytical chemists face multiple complex separations everyday. Very often, complex mixtures containing various compounds need to be analyzed in a single run. Traditional reversed-phase chromatography has challenges for retention of polar-neutral, polar-acidic and polar-basic compounds in mixtures with hydrophobic compounds. We have developed a universal screening method for analysis of complex mixtures containing polar-neutral, polarbasic, polar-acidic, hydrophobic-neutral and hydrophobic-basic compounds. The method employs Primesep 200 mixed-mode reversed-phase cation-exchange column and a simple mobile phase containing ACN/water/sulfuric acid. The low pH of the mobile phase helps suppress ionization of polar-acidic compounds, making them slightly hydrophobic. Hydrophobic and hydrophilic neutral compounds are retained by RP mechanism, while basic hydrophilic and basic hydrophobic compounds are retained by cation-exchange mechanism. Abbreviations: PN-polar neutral, PB-polar basic, PA-polar acidic, HN-hydrophobic neutral, HB-hydrophobic basic

Application Name : Universal HPLC-UV Method for Complex Mixtures

Column Name : Primesep 200 Columns

Analytes : Homovanillic acid, Amitriptyline, Uracil, Toluene, Benzoic acid, Benzylamine, DOPA (3,4-dihydroxy-L-phenylalanine), Phenol, 2,6-Lutidine, Epinephrine Sulfonate, Hydroxytryptophan, Tryptophan, 2,3-DHBA, Methylparaben, Ethylparaben