Retention time calibration for RP-HPLC at pH 9

The change in pH of the mobile phase drastically changes the retention mechanism of peptides, rendering currently available retention time prediction models useless. The aim of this study is to create a dataset of peptide retention times under basic (pH 9) HPLC conditions, allowing for the creation of a retention time prediction model specific for these conditions. Peptides were separated using basic mobile phases and analyzed in positive ion mode, allowing identification with common shotgun proteomics pipeline.