High-performance liquid chromatography of inorgangic and organic ions using low-capacity ion-exchange columns with indirect refractive index detection

Non-UV absorbing inorganic and organic anions and cations may be detected by monitoring the decrease in refractive index of an eluent containing an aromatic counter ion. This approach is applied to the separation and quantitation of a variety of ionic species using commercially available low-capacity high-efficiency ion-exchange columns and conventional high-performance liquid chromatography instrumentation. The results obtained with indirect refractive index detection are compared with indirect UV absorbance and direct conductimetric detection. The analysis of wine for inorganic and organic ionic species is illustrated.