Chemometric evaluation of relationships between retention and physicochemical parameters in terms of multidimensional liquid chromatography of peptides

Statistical evaluation of relationships between chromatographic retention and physicochemical descriptors of peptides was performed. The relationships describing retention were derived for a set of 98 structurally diversified peptides chromatographed on HPLC columns using acetonitrile and water with the addition of 0.1% trifluoroacetic acid as the mobile phase. It was found with the aid of multivariate principal component analysis (PCA) and factor analysis that the retention contributions of the amino acids comprising the individual peptide and the physicochemical parameters describing the bulkiness properties of peptides have the greatest influence on the retention of peptides, independent of the stationary phase used. Retention data were determined on six physicochemically different HPLC columns with the aid of experiments performed with various gradient times and column temperatures. Moreover, PCA permitted differentiation of the RP-HPLC columns used in terms of their similarities and dissimilarities in respect of peptide separations.