This application note describes a method to separate organic acids by ion suppression chromatography (ISC) using reversed-phase liquid chromatography columns and diode array detection. Experiments were performed using a new ZORBAX SB Aq column that successfully separated organic acids. Two standard mixtures of organic acids and a number of soft drinks and wines were analyzed.
The document details a method for separating and analyzing organic acids, such as those found in fruit drinks and wines, using Reversed Phase Liquid Chromatography (RPLC) with Ion Suppression Chromatography (ISC). The method addresses the difficulty of retaining ionized acids under standard RPLC conditions by lowering the eluent pH.
The analysis utilizes an Agilent 1100 series HPLC system equipped with a ZORBAX SB-Aq column, which is specifically designed to operate under completely aqueous and acidic conditions without phase collapse. The note provides experimental details, including chromatographic conditions, sample preparation steps involving filtration, and statistical results regarding reproducibility and linearity for various organic acids.
The minimum detectable amount is 0.24 mg/L.
The flow rate is set to 1.0 mL/min.