Quantitative structure–mobility relationship studies of dipeptides in capillary zone electrophoresis using three-dimensional holographic vector of atomic interaction field

Abstract

To explore the usefulness of empirical models and multivariate analysis techniques in predicting electrophoretic mobilities of dipeptides in capillary zone electrophoresis (CZE), a stepwise multiple regression-multiple linear regression (SMR-MLR) model has been built. The dataset consists of electrophoretic mobilities, measured at pH 2.5, for 53 dipeptides. Among the existing empirical models, the Offord model (i.e., μ = Q/M 2/3) gives the best correlation for the dataset. A quantitative structure–mobility relationship (QSMR) has been developed using the Offord's charge-over-mass term as one descriptor combined with the three-dimensional holographic vector of atomic interaction field descriptors to account for the steric, hydrophobic and electrostatic interactions of the amino acid side chains. The MLR results of the dataset show an improvement in the predictive ability of the model over the simple Offord's relationship.