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Application of solvation model to prediction of the solute retention in liquid chromatography over a wide range of mobile-phase compositions

Jirkal Š., Machovcová M., Ševčík J. G. K.

Acta Chromatographica

2016

Vol. 28, no. 1

59--78

Possibilities have been studied of using a solvation model to predict the retention behavior of solutes in liquid chromatography mobile phases of water-acetonitrile and water-methanol with the organic solvent content varying from 1 to 100 vol%. Twenty-one test solutes, both aliphatic and aromatic compounds, have been selected on the basis of two-level factorial designs. Using the multiple linear regression analysis, regression coefficients, which are characteristics of the stationary and mobile-phase system, were calculated for different mobile phases in the solvation model. Regression coefficients have been used for the prediction of the retention behavior. Unbiased results have been obtained by using two sets, one training and the other the testing set. The predicted retention has been compared with the experimental data. The methanol-water system provided good results at low and medium methanol concentrations; the retention prediction was unsatisfactory for mobile phases containing more than 90% of methanol. The acetonitrile-water system yielded similar results, but the retention prediction ceased to be at acetonitrile concentrations greater than 80%. The retention has primarily been determined by cohesive and acid-base interactions. The dependences of the regression coefficients on the mobile-phase composition were similar for the acetonitrile-water and methanol-water systems.

Semi-empirical equation for the prediction of retention in normal phase liquid chromatography (NP-LC) with polar bonded stationary phases

Zapała W., Zapała L.

Ars Separatoria Acta

2008

No. 6

15-30

A semi-empirical heterogeneous adsorption model for the accurate prediction of analyte retention in a column chromatography with binary mobile phase on polar bonded adsorbent surface was proposed. The performance of the proposed equation was compared with two retention models reported in the literature. All models were verified for different LC systems by means of four criteria: the sum of squared differences between the experimental and theoretical data, approximation of standard deviation, Fisher test and F-test ratio.