High-performance chelation ion chromatography - A new dimension in the separation and determination of trace metals

A review of so-called high-performance chelation ion chromatography (HPCIC) is presented. The principles of this separation technique are based on exploitation of the chelation effect of stationary phases in the presence of comparatively reduced electrostatic ion-exchange interactions, The common ways to suppress ion-exchange, including increasing the ionic strength and pH of the eluent and the column temperature, are discussed. Unlike the majority of low-efficiency chelation exchangers that are used as preconcentration columns for batch separations, HPCIC can be used for high-efficiency analytical separations of trace metals. The range of applications of chelating exchangers used for the separation and determination of alkaline-earth and transition metal ions by HPCIC as well as their types and properties are considered. The main features of HPCIC are the much greater flexibility in selectivity control compared to ion-exchange and the relative insensitivity to high ionic strengths. These properties make it a more preferable technique for the trace analysis of complex samples, such as seawater, saturated brines, etc. (C) 1997 Elsevier Science B.V.