Sorbent-coated metal discs for time-integrated VOC sampling: A reproducible workflow coupled to SPME-GC/MS

Area of Science:

• Analytical Chemistry
• Environmental Science
• Chemical Engineering

Background:

• Direct sampling methods for volatile organic compounds (VOCs) often lack sufficient sensitivity.
• Existing enrichment techniques can be complex, solvent-intensive, or generate significant waste.

Purpose of the Study:

• To develop and validate a time-integrated, reusable platform for VOC enrichment prior to GC/MS analysis.
• To introduce a mass-transport competition framework to explain analyte-dependent performance.
• To provide a solvent-free, low-waste alternative for VOC analysis.

Main Methods:

• Fabrication of sorbent-coated metal discs with a specified sorbent loading.
• Development of a reproducible protocol for disc conditioning, sampling, desorption, and re-adsorption onto SPME fibers.
• Application of a mass-transport competition framework (S = M_ads × η_transfer) to analyze results.

Main Results:

• The sorbent disc workflow demonstrated higher GC/MS peak areas for most analytes compared to direct SPME.
• A reduced response was observed for highly volatile compounds, explained by the mass-transport competition framework.
• The platform proved to be reusable, solvent-free, and compatible with standard GC/MS instrumentation.

Conclusions:

• The developed sorbent disc platform offers a capacity-driven approach for enhanced VOC enrichment.
• The mass-transport framework provides a theoretical basis for understanding and optimizing the enrichment process.
• This method presents a sustainable and efficient alternative for trace VOC analysis.