Prediction of high-performance liquid chromatography retention of peptides with the use of quantitative structure-retention relationships.

Quantitative structure retention relationships (QSRR) were derived allowing prediction of reversed-phase high-performance liquid chromatography (HPLC) retention of peptides. To quantitatively characterize the structure of a peptide, and then to predict its gradient retention time under given HPLC conditions, the following descriptors are employed: logarithm of the sum of retention times of the amino acids composing the peptide, log Sum(AA), logarithm of Van der Waals volume of the peptide, log VDW(Vol), and logarithm of its calculated n-octanol-water partition coefficient, clog P. The first descriptor is based on a set of empirical data for 20 natural amino acids. The next two descriptors are easily calculated from a structural formula. The predicted gradient retention times are in excellent agreement with the experimental data, determined for a structurally diversified series of 101 peptides. The QSRR equation obtained predicts in a convenient and reliable manner the retention times for any peptide in a once characterized HPLC system.