Introducing samples directly into electrospray ionization mass spectrometers by direct infusion using a...

Area of Science:

• Analytical Chemistry
• Biochemistry

Background:

• Direct infusion mass spectrometry requires sensitive interfaces for analyzing complex biological samples.
• Traditional electrospray ionization (ESI) methods often involve higher flow rates, potentially limiting sensitivity for certain applications.

Purpose of the Study:

• To describe the construction and application of a microscale electrospray interface.
• To demonstrate a method for direct sample infusion into mass spectrometers with enhanced sensitivity.

Main Methods:

• Development of a microscale electrospray interface.
• Direct infusion of purified peptide and protein samples into a mass spectrometer.
• Optimization of sample solution flow rate.

Main Results:

• The microscale electrospray interface allows for greatly reduced sample solution flow.
• Analyte signal intensity is preserved despite reduced flow rates, leading to enhanced sensitivity.
• The method proved effective for analyzing individual purified peptide and protein samples.

Conclusions:

• The developed microscale electrospray interface offers a simple and robust method for direct sample infusion.
• This technique is suitable for sensitive analysis of purified peptides and proteins without the need for prior liquid chromatography separation.