Peptide Emulsion - UPLC?
Hello all,I am working on a sample which is comprised of a very hydrophobic peptide in an emulsion (oil:water:detergent mixture). There's about 1% oil (olive or castor oil) and 1% detergent (polysorbate 80/tween 80) with some other additives as well. I am trying to develop a fairly rapid UPLC method for assay and impurity (related peptides, degraded peptides) analysis. If I simply dilute the sample in organic and inject onto a BEH C18 column, the separation is initially pretty good, but the resolution quickly diminishes with time. I guess all the lipid and detergent fouls the column. If I have to add extensive column washing and/or sample preparation steps, I might as well go back to the older HPLC method that we have. Anyone have any suggestions or experiences? Thanks for your help.Steve