I am trying to detect FITC-derivatized peptides with CE (LIF detection). My samples are in a high ionic strength matrix, so I am using 100 mM borate and 60 mM SDS as the electrolyte buffer (SDS to help separate out peptides with similar amino acid sequences). Applied voltage I am using is +23kV and capillary dimensions are 50 um ID x 50 cm effective length.

Can anyone recommend a sample stacking procedure (in detail) so that I don't get band broadening? I have read about acid stacking - would this work? I would like to combine the stacking procedure with large volume injections (approx 60% of effective capillary length) to increase sensitivity...

Thanks for any input you might have....

folive