Direct Biofluid Analysis Using Hydrophobic Paper Spray Mass Spectrometry

Area of Science:

• Analytical Chemistry
• Biochemistry
• Materials Science

Background:

• Current biofluid analysis methods often require extensive sample preparation and specialized equipment.
• There is a need for rapid, sensitive, and quantitative analytical techniques for point-of-care applications.

Purpose of the Study:

• To develop and validate a novel ambient electrostatic paper spray ionization technique for direct biofluid analysis.
• To demonstrate the method's capability for rapid extraction and sensitive detection of small organic compounds and biomarkers.

Main Methods:

• Utilized a hydrophobic paper triangle with applied DC potential for ambient electrostatic paper spray ionization.
• Implemented online liquid/liquid extraction with an organic spray solvent for in situ analysis of biological fluids.
• Analyzed small volumes (4 μL) of raw blood, serum, and urine for illicit drugs and alanine transaminase enzyme activity.

Main Results:

• Achieved rapid online extraction and electrostatic-spray ionization in under 1 minute.
• Demonstrated high sensitivity and quantitative accuracy for illicit drug detection in various biofluids.
• Successfully monitored alanine transaminase enzyme activity, a biomarker for liver injury.

Conclusions:

• The developed paper spray ionization method offers a simple, rapid, and sensitive approach for direct biofluid analysis.
• This technique is highly applicable for point-of-care diagnostics, enabling quick screening and monitoring of health conditions.
• The method shows promise for therapeutic drug monitoring and disease biomarker detection in resource-limited settings.