The mixture of alkylsulphonates was separated and detected indirectly by using 10-(2-dimethylaminopropyl)phenothiazine hydrochloride as a UV-absorbing counter ion. The influence of concentration of counter ion, pH of the mobile phase and the amount of organic modifier on chromatographic behavior of the selected samples of alkylsulphonates was studied on C₂-type stationary phase. The results were compared with data obtained by using of stationary phase modified with phenyl groups.