Ion chromatographic determination of organic acids in vinegar samples using cetyltrimethylammonium ion coated graphite carbon column

From the viewpoint of a graphite carbon column with excellent durability, it was applied to the ion chromatography of several organic acids. The carbon column was permanently coated with the cetylmethylammonium ion, and the elution behaviors of several organic acids and inorganic anions (acetic acid, lactic acid, succinic acid, malic acid, tartaric acid, citric acid, Cl−, NO2−, NO3−) were examined according to an ion chromatography that combined conductometric detection using a mobile phase of the salicylic acid system, when an ion-exchange ability was given to the graphite carbon column. Though the peaks overlapped among Cl−, NO2− and malic acid, it was possible that 9 components were separated within 15 minutes. The calibration curve of each ion was over 0.999 with the correlation coefficient (r2), and the relative standard deviations (RSD) by repeated measurements were found tobe 0.53∼1.03% (n = 6) with good reproducibilities. Analytical results for organic acids, that were contained in food vinegar, were examined using the proposed method. It was possible to get within 1.0% and good values were obtained that comparied with a reversed phase-high performance liquid chromatography (HPLC) using ODS column.