Desorption of Air Samples from ORBO Tubes using the PeakMaster

Importance of Topic

The efficient recovery and analysis of volatile compounds from air sampling media is critical in environmental monitoring, indoor air quality assessment, and product performance evaluation. Thermal desorption directly from adsorbent tubes minimizes sample handling, reduces contamination risk, and ensures quantitative transfer of target analytes into analytical instruments.

Study Objectives and Overview

This application examines the performance of the CDS Analytical PeakMaster EV thermal desorption system equipped with an ORBO tube interface. Two case studies are presented: 1) kinetics of fragrance release from wetted kitty-litter samples monitored via ORBO tubes packed with activated coconut charcoal, and 2) polymer additive identification in silver-based screen-printing inks using GC–IR hyphenated technology.

Methodology and Instrumentation

This work utilizes the PeakMaster EV coupled to:

• ORBO air sampling tubes (activated coconut charcoal), EPA T0-1/T0-2 compliant
• Helium purge at 30 ml/min, desorption temperature 150 °C for 10 min
• Tenax trap for secondary enrichment, back-flushed onto a 30 m GC column (0.52 mm i.d., SE-54)
• Temperature-programmed GC separation (30 °C hold, ramp 6 °C/min to 250 °C)
• Full-range FTIR detector hyphenated to GC for polymer/additive identification

Main Results and Discussion

In the fragrance experiment, air above wetted litter was sampled at 1 min, 30 min and 60 min intervals. Chromatographic profiles reveal that individual fragrance components peak at distinct times, demonstrating variable volatilization rates and temporal masking performance.
In the polymer analysis example, GPC-IR hyphenation separated complex ink components and captured infrared spectra for monomers, oligomers and additives. Three key substances were identified: Polymer A (aliphatic polyester resin), Polymer B (aliphatic polyurethane), and Additive C (ketoxime-blocked HDI trimer). Infrared band patterns confirmed molecular structures and latent cross-linker functionalities relevant in ink curing.

Benefits and Practical Applications

The PeakMaster EV ORBO interface enables:

• Complete and reproducible desorption of volatiles directly from sampling tubes
• Reduced manual transfer steps and improved laboratory throughput
• EPA-compliant sampling for environmental and occupational air monitoring
• Combined GC–IR provides structural insight into complex polymer formulations and additive identification

Future Trends and Opportunities

Advances in thermal desorption automation, miniaturized trap designs, and multidimensional hyphenated detectors will broaden application scope. Integration with high-resolution mass spectrometry and real-time monitoring platforms promises enhanced sensitivity and rapid decision-making in environmental safety, product development and quality control.

Conclusion

The CDS Analytical PeakMaster EV thermal desorption system, with its specialized ORBO tube interface and coupling to GC–IR, delivers robust, EPA-compliant desorption and high-fidelity analysis of volatile organic compounds and polymer additives. This approach streamlines workflows, ensures quantitative recoveries, and provides critical molecular information for both environmental and industrial applications.