Abstract: A method of separating and analyzing slightly volatile cations and/or anions contained in a sample immediately and simultaneously. The sample is injected into a chromatography device in liquid phase co-operating with at least one stationary phase likely to retain the cations and the anions contained in the sample by competing interactions with the stationary phase or phases. The cations and anions are eluted by feeding at least one mobile phase which can be evaporated through the stationary phase or phases. The cations and the anions present in the mobile phase or phases are analyzed with the aid of an evaporative light scattering detector.