[Preliminary exploration of energy transfer about sample ionization process in electrospray ionization source]

Area of Science:

• Analytical Chemistry
• Physical Chemistry

Background:

• Electrospray ionization (ESI) is a versatile technique for detecting molecules ranging from small compounds to large biomolecules like proteins and peptides.
• Current theories do not fully elucidate the complex interplay of forces during the ionization and vaporization processes.

Purpose of the Study:

• To propose a novel energy transfer theory for electrospray ionization (ESI) based on the lowest energy principle.
• To systematically analyze the ionization processes, including analyte transfer from liquid to gas phase.

Main Methods:

• Systematic analysis of ionization processes in ESI.
• Application of energy transfer theory based on the lowest energy principle.
• Examination of the influence of multiple forces (electrostatics, van der Waals') on analyte transfer.

Main Results:

• The proposed energy transfer theory simplifies existing theories and explains solvent and electrolyte ion effects.
• Analyte transfer is governed by a balance of forces, with Gibbs free energy influencing ion evaporation and multiply charged macromolecule formation.
• Competition exists between evaporation and multi-charge ion formation.

Conclusions:

• The energy transfer theory provides a foundational understanding of ESI mechanisms.
• This theory can optimize detection conditions for diverse samples.
• It offers insights into the fundamental processes of ionization in ESI.