Ethylene glycol improves electrospray ionization efficiency in bottom-up proteomics

Area of Science:

• Analytical Chemistry
• Biochemistry
• Proteomics

Background:

• Nano-electrospray ionization (nESI) coupled with liquid chromatography tandem mass spectrometry is crucial for proteome research.
• Dimethyl sulfoxide (DMSO) has previously demonstrated a 3-10x improvement in nESI efficiency, enhancing proteomic experiment sensitivity and coverage.

Purpose of the Study:

• To systematically screen various compounds for their ability to enhance nESI response at a proteomic scale.
• To evaluate ethylene glycol as a potential alternative to DMSO for improving peptide ionization efficiency.

Main Methods:

• Screening of approximately 30 compounds with diverse physico-chemical properties.
• Detailed analysis of promising solvent additives, including ethylene glycol.
• Evaluation of nESI efficiency and peptide ionization enhancement.

Main Results:

• Ethylene glycol demonstrated performance comparable to DMSO in enhancing nESI response.
• The study confirmed that simple solvent additives can effectively enhance peptide ionization for proteomic analysis.
• Key properties for effective solvent additives include high boiling point, low surface tension, and high polarity.

Conclusions:

• Enhancing nESI response with solvent additives is a valid and promising approach for proteomic research.
• Ethylene glycol serves as a viable alternative to DMSO, particularly in applications where DMSO may be disadvantageous.
• The findings support the use of ethylene glycol for improving peptide ionization and overall proteomic data quality.