POST-IONISATION AND FRAGMENTATION OF GAS-PHASE IONS FOR SINGLE ORGANISM ANALYSIS (PIFAGOR)

Biological mass spectrometry (BioMS) is based on volatilization and ionization of compounds of interest and measuring their mass-to-charge ratios.

In order to derive structural information, the gas-phase ions are dissociated in tandem mass spectrometry (MS/MS) into fragments by collisions with neutrals, electrons or photons.

The process of ion activation and dissociation of fundamental importance in MS/MS, and it has traditionally been focused on large molecules.

The recent emergence of single-cell proteomics and metabolomics requires refocusing the MS/MS development efforts to smaller molecules, such as peptides and lipids, for which extreme sensitivity is required.

Here we envision a new MS/MS platform (Post-Ionization and Fragmentation of Gas-phase ions for Single Organism Analysis, PIFAGOR) for proteomics and metabolomics of single cells and small organisms, such as C. Elegans, a popular model organism in Molecular biology.

In PIFAGOR, the ionic charge state of precursor ions will be increased by electron impact concomitantly with dissociation.

The total charge of ionic fragments in such electron ionization dissociation  (EID) MS/MS will be larger than the original charge of the precursor ions, thus achieving ≥100% fragmentation efficiency.

Also, novel liquid phase separation online with new fragmentation methods such as Coulomb explosion will be implemented. Achieving this would be a fundamental accomplishment for BioMS and its applications in biomedical sciences.