Ultra-fast HPLC separation of common anions using a monolithic stationary phase

In this work, a monolithic column was used to perform ultrafast separations of common inorganic anions in as little as 15 seconds. Separations were performed using ion-interaction chromatography with tetrabutylammonium-phthalate as the ion-interaction reagent and were monitored using either direct conductivity or indirect absorbance detection. Detection limits for direct conductivity were in the low ppm range, whereas those for indirect absorbance detection were up to an order of magnitude higher. The reproducibility was 0.4% and 2% RSD for retention time and peak area, respectively, for a one minute separation, and 2.8% and 3-15%, respectively, for the 15 second separation. The proposed method was validated versus standard ion chromatography with suppressed conductivity detection for the analysis of an industrial water sample.