peptide retention time

Is peptide RT charge specific?
"Not in the sense that ESI-charge is influencing the retention time but
in the sense that longer peptide tend to elute later in the
chromatogram and also are more likely to have higher charge states,
there is a slight correlation between charge state and retention time.
however it would work as prediction tool if you consider predicting
the charge state of a peptide, which is actually not that difficult to
do." by Hannes.