ANALYSIS OF HUMAN CELL LINES USING AUTOMATIC TUBE EXCHANGE (ATEX) AND GC/MS

Significance of the Topic

Monitoring volatile organic compounds emitted from human cell lines provides valuable insights into cellular metabolism and potential biomarkers of disease. Traditional sample introduction methods often suffer from contamination of the inlet system by non-volatile matrix components, reducing analytical robustness. Automated Tube Exchange (ATEX) coupled with thermal desorption and GC/MS offers a streamlined, reproducible approach to isolate and measure volatiles from complex biological matrices without fouling the inlet.

Objectives and Study Overview

The primary aim of this work was to develop and validate an automated workflow for the analysis of volatile analytes from pelleted human cell lines using ATEX and GC/MS. Two distinct cell line pellets, provided at two concentration levels, were compared. Key goals included verifying the absence of carryover, establishing reproducibility of measurement, and identifying discriminating volatile markers between cell lines.

Methodology and Instrumentation

Pelleted cell line samples were stored on dry ice and introduced directly, in microvials, into a Thermal Desorption Unit (TDU) via Automated Tube Exchange on a GERSTEL MultiPurpose Sampler (MPS). Thermal desorption transferred volatiles onto a cooled inlet system (CIS-4), then onto a GC column. Both single quadrupole and GC/Q-TOF mass spectrometers (Agilent 7890/5975 and 7890B/7200) were employed with MassHunter and Mass Profiler Professional software. The ATEX method prevented non-volatiles from entering the inlet liner, preserving system cleanliness.

Used Instrumentation

• GERSTEL Dual Head MultiPurpose Sampler (MPS) XT
• GERSTEL TDU using ATEX
• GERSTEL CIS-4 with Tenax
• Agilent GC/MS 7890/5975
• Agilent GC/Q-TOF 7890B/7200

Main Results and Discussion

No significant carryover was observed when comparing cell line desorption to blank runs. Principal Component Analysis clearly separated Sample A, Sample B, and blanks, indicating robust discrimination. Tentative identification of key volatiles—such as indole, dodecanamide, cholesterol, palmidrol, and an oxazole derivative—was achieved by library matching and accurate mass (<5 ppm) confirmation. Replicate analyses showed relative standard deviations of approximately 18–20% for principal peaks. Extracted ion chromatograms (e.g., m/z 98) highlighted concentration differences between cell lines.

Benefits and Practical Applications

• Enhanced system robustness by excluding non-volatile residue from the inlet liner.
• Automated, high-throughput sample introduction reduces manual handling and variability.
• Clear differentiation of cell line metabolic profiles enables biomarker discovery.
• Adaptable workflow for quantitative analysis with the incorporation of internal standards.

Future Trends and Applications

Integration of ATEX with high-resolution mass spectrometry and advanced data analytics will further refine biomarker identification. Expansion to untargeted metabolomic studies and clinical diagnostics is anticipated. Automation and miniaturization of thermal desorption platforms may facilitate on-site or point-of-care volatilomics.

Conclusion

The combined ATEX and GC/MS approach provides a robust, automated solution for analyzing volatile compounds in human cell line pellets. This method enables clean inlet operation, reliable reproducibility, and effective discrimination of cell line profiles. Future adaptation with internal standards promises quantitative capability for targeted biomarker assays.

Reference

No external literature references were provided in the source document.