ISOCRATIC AND GRADIENT CONDITIONS FOR INORGANIC CATIONS ANALYSIS BY REALIZATION ON-LINE COUPLING OF ION EXCHANGE CHROMATOGRAPHY WITH EVAPORATIVE LIGHT SCATTERING DETECTOR
Performances of three available commercials cationic exchangers: Lichrosil IC CA2 Merck, Metrosep cation 1-2 Metrohm and PRP-X200 Hamilton for ion exchange chromatography were compared. Isocratic conditions were developed for inorganic cations (Na+, K+, Mg2+ and Ca2+) separation on Metrosep cation 1-2 and Lichrosil IC CA2 columns in about 6 min and 3 min, respectively using proton as ion developer. While, ammonium was used as ion developer for inorganic cations separation with step gradient on PRP-X200 Hamilton column in about 10 min. Retentions of inorganic cations on these chromatographic supports were discussed. Evaporative light scattering detector was used as detection system. The developed method provides good linearity for the calibration curves, and enables a 10 ng absolute detection limit for Na+, Mg2+ and Ca2+ and a 25 ng absolute detection limit for K+, at a signal-to-noise ratio of 3.
