Abstract
A suppressed ion method for the determination method of eight organic acids (formic, malonic, lactic, acetic, malefic, citric, fumaric, and propionic acid) has been studied for reversed-phase high-performance liquid chromatography (RP-HPLC) with a new triacontyl groups (C30) column, coupled with an ultraviolet detector (UV) at 210 nm. A 50 mM ammonium dihydrogenphosphate (NH4H2PO4) aqueous solution (pH 2.0) containing phosphoric acid (H3PO4) was used as an optimal mobile phase for the separation of eight organic acids. A good linearity of the calibration curve was obtained in the concentration range of 5 mgl-1 to 100 mgl-1 (|r| =0.9999-0.9994) . The detection limit based on S/N=3 were 3.8 mgl-1 for formic acid, 3.5 mgl-1 for malonic acid, 3.1 mgl-1 for lactic acid, 3.4 mgl-1 for acetic acid, 1.1 mgl-1 for maleic acid, 3.4 mgl-1 for citric acid, 3.3 mgl-1 for fumaric acid, and 3.6 mgl-1 for propionic acid. This analytical method was successfully applied to the determination of eight organic acids in sake and wine.
