Thermal desorption solutions

Significance of the Topic

Thermal desorption (TD) represents a pivotal advance in gas chromatography sample introduction, enabling direct, solvent‐free transfer of volatile and semivolatile organics from diverse matrices into GC or GC/MS systems. Its high sensitivity, automation potential, and broad compatibility make TD indispensable for environmental monitoring, material emissions testing, and flavor/fragrance profiling.

Study Objectives and Overview

This whitepaper outlines the integration of Agilent’s GC/MS expertise with Markes International’s state-of-the-art TD platforms. The goal is to present a unified, fully supported solution that maximizes analytical performance, operational efficiency, and method compliance across laboratory workflows.

Methodology and Instrumentation

TD directly desorbs analytes from sorbent tubes into a GC inlet, eliminating labor‐intensive solvent extractions. Key instruments include:

• UNITY-xr: Single-tube desorption with cryogen-free focusing to –30 °C, quantitative re-collection of split flows, RFID support, and upgradable automation.
• TD100-xr: Automated handling of up to 100 tubes with “50:50” re-collection, onboard tag read/write, and stringent leak testing.
• Air Server-xr and CIA Advantage-xr: Canister and online air/gas sampling for continuous monitoring in mobile or fixed labs.
• ULTRA-xr: Compact autosampler for up to 100 capped tubes with optional standard addition.
• μ-CTE and TC-20: Micro-chamber thermal extractor for small samples and multi-tube conditioner/dry purge unit to prepare sorbent tubes efficiently.

All platforms feature inert flowpaths for quantitative recovery of C2–C44 compounds and integration with MassHunter/OpenLab CDS.

Main Results and Discussion

TD systems demonstrate over 95 % recovery, sub-ppt detection limits, and robust retention of reactive or thermally labile species. Cryogen-free operation reduces operating costs and maintenance. Overlap desorption mode and electronic pneumatic controls enhance throughput and reproducibility.

Benefits and Practical Applications

TD technology offers significant advantages for:

• Air Monitoring: Ambient, stack, indoor, personal exposure, and photochemical assessments compliant with TO-15/TO-17 and EN methods.
• Material Emissions: VOC release testing from construction materials, coatings, furnishings, and electronics.
• Flavor and Fragrance: Aroma profiling, off-odor detection, and repeat analysis for validation.
• Defense and Forensics: Trace analysis of explosives, accelerants, drugs, and chemical threats.

Future Trends and Opportunities

Advancements will focus on enhanced automation, real-time online monitoring, smart tube tagging, and cloud-based data management. Integration with laboratory information management systems and multiplexed sampling promises to further streamline high-throughput analyses.

Conclusion

The collaboration between Agilent and Markes International delivers a unified TD-GC/MS solution that elevates sensitivity, efficiency, and compliance. By leveraging innovative instrumentation and comprehensive support, laboratories can address a wide array of analytical challenges with confidence.