Pulsed Direct Current Arc-Induced Nanoelectrospray Ionization Mass Spectrometry

Area of Science:

• Analytical Chemistry
• Biochemistry
• Mass Spectrometry

Background:

• Electrospray ionization (ESI) is a crucial technique in mass spectrometry.
• Developing novel ionization sources can improve sensitivity and provide new analytical capabilities.

Purpose of the Study:

• To introduce and evaluate pulsed direct current arc-induced nanoelectrospray ionization mass spectrometry (DCAI-nano-ESI-MS).
• To demonstrate the utility of DCAI-nano-ESI-MS for analyzing biological molecules and elucidating lipid structures.

Main Methods:

• Utilized a low-temperature direct current (DC) arc to induce electrospray ionization (ESI) in a mass spectrometry (MS) setup.
• Employed a 15 kV output voltage for the DCAI-nano-ESI source.
• Analyzed various biological molecules including peptides and lipids.
• Investigated fatty acid oxidation and phosphatidylcholine structural analysis.

Main Results:

• DCAI-nano-ESI-MS effectively identified peptides like angiotensin II, bradykinin, and cytochrome C, and lipids such as soybean lecithin.
• The method produced significant analyte signals and facilitated multicharge mass spectrometry (MS) in both positive and negative ion modes.
• Fatty acid oxidation via DC arc generated specific ions aiding in C═C bond localization and isomer differentiation.
• Accurate determination of phosphatidylcholine molecular configurations and *sn*-positions was achieved.

Conclusions:

• DCAI-nano-ESI-MS is a promising technique for sensitive analysis of diverse biological molecules.
• This method provides valuable structural information for fatty acids and phospholipids.
• DCAI-nano-ESI holds significant potential for future analytical and bioanalytical applications.