Post-column solvent addition enhances sensitivity of microflow-based bottom-up proteomics

We demonstrate that post-column addition of organic solvents leads to a strong enhancement of electrospray stability in microflow LC-MS experiments improving the sensitivity across the entire gradient, for early eluting peptides by up to tenfold. Post-column solvent addition did not negatively affect chromatographic performance and resulted in an overall 28%-36% increase in identifications at both protein- and peptide-level. Post-column solvent addition can be easily adopted on any microflow LC-MS/MS system.