Česká společnost pro hmotnostní spektrometrii

(13. ročník České konference hmotnostní spektrometrie a 11. Neformální proteomické setkání - ThS-07)
Propionic acid boosts sensitivity in high-flow RPLC-MS proteomics compared to formic and acetic acid

Mykyta R. Starovoit ¹, Siddharth Jadeja ¹, Derya Demir ¹, Rudolf Kupčík ², Juraj Lenčo ^1 *

1. Charles University, Faculty of Pharmacy in Hradec Králové
2. Biomedical Research Centre, University Hospital Hradec Králové, Sokolská 581, 500 05 Hradec Králové

Abstrakt

Formic acid has long been the default acidic additive in mobile phases for RPLC-MS-based bottom-up proteomics due to its balance between chromatographic performance and electrospray ionization (ESI) efficiency, while most efforts to improve sensitivity have rather focused on sample preparation and MS instrumentation. However, recent studies have revived interest in acetic acid, revealing that its lower ionic strength enhances ESI efficiency without sacrificing chromatographic performance. Inspired by this concept, we investigated propionic acid, a homologous compound that was overlooked as a mobile phase additive. By further weakening ionic strength and lowering mobile phase surface tension, propionic acid yielded an average 12% increase in peptide identifications over acetic acid across interlaboratory datasets using analytical- and microflow LC-MS platforms, various column chemistries, and levels of sample complexity. Importantly, chromatographic performance remained virtually unaffected, with only a modest decrease in retention. The mobile phase containing propionic acid was stable, instrument-safe, and introduced negligible MS background noise. These findings challenge the long-standing reliance on formic acid and establish propionic acid as a potent, drop-in alternative for high-flow LC-MS workflows prioritizing detection sensitivity and depth of proteome coverage.

* Korespondující autor: lenco@faf.cuni.cz

Poděkování:

This study was supported by the Project of the Czech Science Foundation (GAČR No. 22-21620S), the Project of the Charles University Grant Agency (GAUK No. 370522), the SVV Project No. 260782, and the project New Technologies for Translational Research in Pharmaceutical Sciences (NETPHARM, No. CZ.02.01.01/00/22_008/0004607) co-funded by the European Union.