Paper-based sample processing for the fast and direct MS analysis of multiple analytes from serum samples

Area of Science:

• Biochemistry
• Analytical Chemistry
• Biomedical Engineering

Background:

• Amino acids are crucial biomarkers for human health and disease diagnosis.
• Rapid and accurate determination of amino acids is essential for timely medical intervention.
• Existing methods for amino acid analysis can be time-consuming and require complex sample preparation.

Purpose of the Study:

• To develop a novel, rapid, paper-based sample-processing device for amino acid analysis.
• To combine this device with isotope-dilution mass spectrometry (IDMS) for efficient blood sample analysis.
• To achieve fast separation and purification of target amino acids from complex biological matrices.

Main Methods:

• Utilized a paper-based device with isoelectric focusing electrokinetic separation.
• Established a stable pH gradient (pH 3-10.5) on glass-fiber paper using a MS-friendly electrolyte.
• Employed DC voltage for separation and concentration of amphoteric species within 2 minutes.
• Applied the method to both liquid and dry spot blood samples for direct IDMS detection.

Main Results:

• Achieved separation and purification of 11 amino acids from blood samples.
• Demonstrated a 20-fold increase in speed compared to commercial kit methods.
• Successfully concentrated amino acids into a narrow band for direct MS detection.
• Validated the method for both liquid and dry spot blood samples.

Conclusions:

• The developed paper-based device coupled with IDMS offers a rapid and efficient strategy for amino acid analysis.
• This approach significantly reduces analysis time and sample preparation complexity.
• It presents a promising tool for rapid, on-site diagnosis and monitoring of diseases related to amino acid metabolism.