SICRIT® -HRMS for Exhaled Breath Analysis

Importance of the Topic

This study addresses non-invasive monitoring of volatile organic compounds (VOCs) in exhaled breath, a rapidly growing field in clinical diagnostics. Breath biomarkers reflect metabolic and inflammatory processes linked to respiratory diseases, oxidative stress and systemic conditions such as diabetic ketoacidosis. Real-time profiling enhances patient comfort and diagnostic speed, with additional applications in food science for aroma metabolism analysis.

Objectives and Study Overview

The primary aim was to demonstrate how the SICRIT ion source can be seamlessly adapted to high-resolution mass spectrometry (HRMS) for trace-level breath analysis. A proof-of-concept evaluation with healthy volunteers assessed ionization performance, spectral detail and the feasibility of plug & play integration for real-time VOC detection.

Applied Methodology and Instrumentation

The SICRIT ionization source was connected to a Thermo Fisher LTQ Orbitrap XL via an atmospheric pressure inlet. Exhaled breath was conveyed through a custom stainless steel tube enclosed in a heated hose at 150 °C to prevent condensation. The airflow was maintained at 7.5 L/min with nitrogen dilution, using disposable mouthpieces. MS acquisition employed full-scan positive mode at 30 000 FWHM over 50–300 m/z, with data processed at ±5 ppm mass accuracy. Three consecutive exhalations were recorded per session.

Main Results and Discussion

Reproducible total ion current peaks corresponded to individual breath cycles, confirming stable sampling. Detected compounds included acetone, urea, pyridine, indole and various aldehydes associated with oxidative stress. Amino acids such as leucine, isoleucine, proline and valine were also identified, showcasing the broad polarity range and soft ionization capability of SICRIT.

Benefits and Practical Applications

SICRIT-HRMS enables rapid, high-sensitivity breath analysis without extensive sample preparation. Its plug & play design allows swift integration into existing LC-MS systems. The technique supports clinical diagnostics, metabolic research and can be combined with chromatography or direct liquid injection for comprehensive biomarker profiling.

Future Trends and Potential Applications

Emerging developments may include portable HRMS devices for point-of-care testing, integration with machine learning algorithms for automated pattern recognition and expanded use in environmental monitoring and food quality assessment. Miniaturization and real-time data processing will drive broader adoption.

Conclusion

The SICRIT ion source coupled to HRMS delivers a versatile, sensitive platform for non-invasive exhaled breath analysis. Its high selectivity, soft ionization and easy interfacing position it as a valuable tool for clinical and industrial applications. Ongoing advancements will further solidify its role in routine breathomics.

Reference

• A Amann et al Journal of Breath Research 2014 8(3) 034001
• MT Gaugg et al CHEST 2019 156(2) 269-276
• G Pugliese et al Analyst 2019 144 7359-7367