@seejbrown @ProteomicsNews @chrashwood For labile PTM's keep the KE low and a reaction time of around 10-20ms. Higher the charge state of the precursor the better. I managed to localise a phosphorylation site on a 8kDa peptide as it was a 5+ ion and fell apart easily with 2eV.
@r_l_moritz@ucdmrt @chrashwood At Dundee we had a Sepharose 4B column that was used for over 15 years to purify phosphorylase kinase (1.6MDa). It was 2m long and definitely not single use.