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

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

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.

___

  • 1.Kim, S.K., Jung, M.Y., Kin, S.Y., Photodecomposition of aspartame in aqueous solutions, Food Chem., 59, 273, 1997.
  • 2.Prudel, M., Davıdkovâ, E., Davidek, J., Kminek, M., Kinetics of decomposition of aspartame hydrochloride (Usal) in aqueous solution, J. Food Sci., 51(6), 1393, 1986.
  • 3.Homier, B.E., Properties and stability of aspartame, Food Technol., 38(7), 50, 1984.
  • 4.Sabah, S., Scriba, G.K.E., Determination of aspartame and its degradation and epimerization products by capillary electrophoresis, J. Pharm. Biomed. Anal., 16, 1089,1998.
  • 5.Stenberg, M., Marko-Varga, G., Oste, R., Racemization of amino acids during classical and microwave oven hydrolysis - application to aspartame and a Maillard reaction system, Food Chem., 74, 217, 2001.
  • 6.Hsieh T.J., Chen, S., A facile HPLC method for optical purity and quantitative measurements of phenylalanine from the hydrolyzed aspartame under different pH and temperature after its derivatization with a fluorescent reagent, Amino Acids, 33, 123, 2007.
  • 7.Bell, L.N., Wetzel, C.R., Aspartame degradation in solution as impacted by buffer type and concentration, J. Agric. Food Chem., 43, 2608, 1995.
  • 8.Lawrence, J.F., Iyengar, J.R., Liquid chromatographic determination of beta-aspartame in diet soft drinks, beverage powders and pudding mixes, J. Chromatogr., 404,261,1987.
  • 9.Verzella, G., Bagnasco, G. and Mangia, A., Ion-pair high-performance liquid chromatographic analysis of aspartame and related products, J. Chromatogr., 849, 83, 1985.
  • 10.Gaines, S.M., Bada, J.L., Reversed-phase high-performance liquid chromatographic separation of aspartame diastereomeric decomposition products, J. Chromatogr., 389, 219, 1987.
  • 11.Tsang, W.S., Clarke, M.A., Parrish, F.W., Determination of aspartame and its breakdown products in soft drinks by reverse-phase chromatography with UV detection, J. Agric. Food Chem., 33, 734,1985.
  • 12.Stamp, J.A., Labuza, T.P., An ion-pair high performance liquid chromatographic method for the determination of aspartame and its decomposition products, J. Food Sci., 54(4), 1043, 1989.
  • 13.Demiralay, E.C., Özkan, G., Optimization strategy for isocratic separation of a-aspartame and its breakdown products by reversed phase liquid chromatography, Chromatographia, 60 (9/10), 579, 2004.
  • 14.Rondinini, S., Mussini, P.R., Mussini, T., Reference value standards and primary standards for pH measurements in organic solvents and water+organic solvent mixtures of moderate to high permittivities, Pure Appl. Chem., 59, 1549, 1987.
  • 15.Sanli, N., Fonrodona, G., Barbosa, J., Özkan, G.A., Beltran, J.L., Modelling retention in liquid chromatography of polyphenolic acids Prediction of solvent composition and pH of thve mobile phase, Anal. Chim. Acta, 537, 53, 2005.
  • 16.Barbosa, J., Marques, I., Baron, D., and Sanz-Nebot, V., The application of factor analysis to solvatochromic parameters and pHs values for the standardization of potentiometric sensors in mobile phases used in liquid chromatography, Trends Anal. Chem., 18(8), 543,1999.
  • 17.Barbosa, J., Sanz-Nebot,V., Assignment of reference pH-values to primary standard buffer solutions for standardization of potentiometric sensors in acetonitrile-water mixtures, Fresenius J. Anal. Chem. 353,148,1995.
  • 18.Snyder, L.R., Kirkiand, J.J., Glajch, J.L. Practical HPLC Method Development, 2nd ed., Wiley, New York, 1997.
  • 19.Jandera, P., Churacek, J., and Taraba, B., Comparison of retention behaviour of aromatic sulphonic acids in reversed-phase systems with mobile phases containing ion-pairing ions and in systems with solutions of inorganic salts as the mobile phases, J. Chromatogr. 262, 121, 1983.
  • 20.Zou, H., Zhang,Y., Hong,M., Lu, P., Retention behaviour of aromatic sulphonic acids in reversed-phase ion-pair liquid chromatography with methanol and acetonitrile as organic modifiers, Journal of Chromatography A, 644(2), 269, 1993.
  • 21.Zou, H., Zhang,Y., Hong,M., Lu, P., Effects of organic modifier and ion-pair reagent in liquid chromatography, Chromatographia, 35(7/8), 390-394,1993.
  • 22.Horvâth, C., Melander, W., Molnâr, I., Molnâr, P., Enhancement of retention by ion-pair formation in liquid chromatography with nonpolar stationary phases, Anal. Chem., 49, 2295, 1977.
  • 23.Horvâth, C., Melander, W., Molnâr, I., Solvophobic interactions in liquid chromatography with nonpolar stationary phases, J. Chromatogr,. 125, 129,1976.
  • 24.Tilly-Melin, A., Askemark, Y„ Wahlund, K. G„ Schill, G., Retention behavior of carboxylic acids and their quaternary ammonium ion pairs in reversed phase chromatography with acetonitrile as organic modifier in the mobile phase, Anal. Chem., 51, 976, 1979.
  • 25.Szokoli, F., Nemeth, Zs., and Inczedy, J., Selection of optimal pH and solvent composition for the separation of organic acids using three-dimensional diagrams and a computer program, Chromatographia, 29, 265, 1990.
  • 26.Klein, E.J., Rivera, S.L., A review of criteria functions and response surface methodology for the optimization of analytical scale HPLC separations, J. Liq. Chromatogr. Relat. Technol., 23(14), 2097, 2007.
  • 27.Snyder, L.R., Dolan, J.W., Gant, J.R., Gradient elution in high-performance liquid chromatography : I. Theoretical basis for reversed-phase systems, J. Chromatogr. A, 165(1), 3, 1979.
  • 28.Balogh, G.T., Szântö, Z., Forrai, E., Györffy, W., Lopata, A., Use of reversed-phase liquid chromatography for determining the lipophilicity of a-aryl-W-cyclopropyl nitrones, J. Pharma. Biomed. Anal., 39,1057, 2005.
  • 29.Valkö, K., and Slegel, P., New chromatographic hydrophobicity index (_____pg) based on the slope and the intercept of the log k' versus organic phase concentration plot, J. Chromatogr. A, 631, 49, 1993.
  • 30.Hansen, H., Helboe, P., High-performance liquid chromatography on dynamically modified silica. V: Influence of nature and concentration of organic modifier in eluents containing cetyltrimethylammonium bromide, Journal of chromatography, 285, 53, 1984.