Simultaneous detection of monovalent anions and cations using all solid-state contact PVC membrane anion and cation-selective electrodes as detectorsin single column ion chromatography

The overall efficiency of ion chromatographic procedures allows the possibi lity of routine separation and detection of common inorganic and organic an ions and cations at low levels in a simultaneous system. A simple and rapid independent separation, and sensitive simultaneous detection of monovalent common anions and cations were achieved using 2 mM copper sulfate, (at pH: 5.40), as eluent with low cell-volume potentiometric detectors. This was e stablished using all-solid state contact, tubular, PVC-matrix membrane anio n and cation-selective electrodes in series as detectors with mixed-bed ion -exchange column in ion chromatography. The developed method is reproducibl e and highly selective to monovalent anions and cations, and takes less tha n 8 min. Under all operation conditions, the detection Limits of the develo ped method, for potassium, rubidium, cesium, thallium(I), nitrite, nitrate, benzoate and bromide, were of the order of tens of ppb, for sodium, ammoni um, chloroacetate, cyanate and chloride ions, values were of the order of h undreds of ppb for an injected volume of 20 mu l. The method was flexible s ince most of anions do not interfere the detection of cations and most of c ations do not affect the detection of anions, so that the method can be app lied to many sample types e.g. environmental. The application of the method for river, sea and tap water samples were illustrated. (C) 1999 Elsevier S cience B.V. All rights reserved.