Optimization of ion pair reversed phase liquid Chromatography separation of a-aspartame and breakdown productsalpha

Abstract

In this work, the proportion of organic modifier of acetonitrile–water mixtures used as mobile phases were optimized in order to separate the a-aspartame and six breakdown compounds by using the relationships between the retention parameters of the compounds and the percentage of organic modifier. The separation was accomplished under ion pair reversed phase conditions using an YMC ODS AM (250x4.6 mm I.D., 5 μm) column. Optimum mobile phase for the chromatographic separation is composed of acetonitrile-water (20:80, v/v). Concentration of heptanesulfonic acid is 2.$10^ {-3}$ M at this mobile phase and the pH of the mobile phase is 2.60. Chromatographic hydrophobicity parameter and chromatographic hydrophobicity index were also calculated.