Epinephrine and epinephrine sulfonate are separated on combination of Primesep 100 and Primesep SB HPLC columns. Primesep 100 column retains epinephrine by combination of reversed-phase and cation-exchange mechanisms. Epinephrine sulfonate is retained by weak reversed-phase mechanism. Due to strong zwitter-ionic nature of epinephrine sulfonate, ionic interaction is not available for this molecule. Compounds can be monitored by UV, ELSD, CAD or LC/MS.