Quantitative structure-retention molecular properties

A quantitative analysis of the structure-retention relationship can be derived by using the relative solubility of solutes in water. One parameter is the partition coefficient, log P, of the analyte measured as the octanol-water partition distribution. In early work, reversed-phase liquid chromatography was used to measure log P values for drug design. Log P values were later used to predict the retention times in reversed-phase liquid chromatography.The calculation of the molecular properties can be performed with the aid of computational chemical calculations. In this chapter, examples of these quantitative structure-retention relationships are described. 

Retention in chromatographic systems can be connected with the properties of the chromatographed compounds. It should manifest itself in quantitative structure-retention relationships (QSRR) equations, correlating retention parameters (log k) with the properties of analytes and chromatographic system revealed by molecular descriptors dipolarity/polarizability, ability to donate H-bonds, measure of analyte H-bond accepting potency, analyte molecular volume, and others. 

One of the primary application areas for SPR studies is in chromatography. Quantitative relationships between the molecular structures of solutes and their chromatographic retention have been extensively investigated. The field known as Quantitative Structure—Retention Relationships (QSRR) has resulted. Reasons for this interest include the desire to predict retention, investigations of the mechanism of interaaions between solute molecules and the stationary phase, and the attempt to focus on the physicochemical properties of the solute molecules that affect retention and why they have such an effect. Of the three main variables that affect chromatographic retention— solute structure, physicochemical properties of the mobile phase, and physicochemical properties of the stationary phase—the effeas of varying solute... 

This section again covers ab initio, density functional theory (DFT), semi-empirical and empirical calculations, molecular mechanics and molecular dynamics methods. Other interesting theoretical and computational chemistry techniques reported include quantitative structure-retention relationships (QSRR), and quantitative structure-property relationships (QSPR) for the prediction of various physicochemical properties. Again, all areas of theoretical and computational chemistry have continued to expand rapidly. These methods have been used to predict, support and also validate the majority of the observed experimental data. 

Wolf, R. M., Erancotte, E., Lohmann, D., Quantitative correlation between calculated molecular properties and retention of series of structurally related racemats on cellulose triacetate, J.Chem. Soc., Perkins Trans. II, 1988, 893-901. 

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