Paper spray ionization devices for direct, biomedical analysis using mass spectrometry

Area of Science:

• Analytical Chemistry
• Mass Spectrometry
• Separation Science

Background:

• Paper spray ionization (PSI) is a direct, rapid, and cost-effective sampling and ionization technique.
• It is utilized for qualitative and quantitative mass spectrometric (MS) analysis of complex mixtures.
• Analyte ions are generated by applying high voltage to a small volume of spray solvent on a porous substrate.

Purpose of the Study:

• To investigate factors affecting ionization efficiency and quantitation accuracy in PSI.
• To provide guidance for optimizing PSI for disposable sample cartridges.
• To assess the suitability of PSI for rapid clinical analysis and point-of-care diagnostics.

Main Methods:

• Systematic studies on paper geometry (cut angle) and its effect on spray plume and electric field.
• Investigation of sample load and its impact on signal stability and quantitative results.
• Analysis of analyte transfer on paper, correlating it with bulk solution flow.

Main Results:

• Paper tip geometry significantly influences spray characteristics and signal intensity.
• Optimal sample load is dependent on paper size for stable MS signals.
• Analyte transfer is primarily driven by bulk solution flow towards the spray tip.

Conclusions:

• Optimizing paper geometry and sample load is crucial for efficient PSI.
• PSI is a promising technique for developing disposable cartridges for rapid clinical analysis.
• The method shows potential for point-of-care diagnostic applications.