RAPID DETERMINATION OF VOLATILE COMPOUND CONTENT USING MULTIPLE HEADSPACE EXTRACTION-SIFT-MS

Significance of the Topic

The migration of volatile organic compounds from packaging into consumer goods can compromise product quality and safety, particularly in pharmaceuticals and food. Accurate, efficient quantification of these volatiles in materials like paperboard is therefore critical for quality control and regulatory compliance.

Objectives and Study Overview

This application note evaluates a novel approach combining multiple headspace extraction (MHE) with selected ion flow tube mass spectrometry (SIFT-MS) to rapidly and quantitatively measure C1–C10 aldehydes and other oxygenated VOCs in paperboard. The study aims to demonstrate enhanced throughput and broader compound detection compared to traditional GC-MS methods.

Methodology and Instrumentation

• Sample preparation: Replicate paperboard strips (21×4 cm, 1.3 g) incubated in 20 mL vials at 75 °C for 20 min, followed by a 3 min post-flush.
• MHE protocol: Ten consecutive headspace cycles per sample, with SIFT-MS analysis of six initial cycles for concentration calculations, based on exponential decay of headspace concentrations.
• SIFT-MS conditions: Headspace samples withdrawn by heated syringe (150 °C), injected at 50 µL/s into the SIFT-MS inlet with total flow ~420 µL/s.
• Instrumentation: Selected ion flow tube mass spectrometer equipped with GERSTEL PrepAhead automation for parallel MHE processing.

Main Results and Discussion

Headspace concentrations for target volatiles demonstrated excellent linearity across MHE cycles, confirming the exponential decay model. Repeatability (RSD) was generally below 10 % even at low ppb levels, increasing slightly for less volatile compounds. Calculated paperboard concentrations ranged from sub-µg/g to tens of µg/g for compounds such as acetaldehyde, propanal, nonanal and decanal. This aligns closely across replicate analyses and with conventional GC-MS methods.

Practical Benefits and Applications

• Throughput: Fourfold increase in sample throughput versus MHE-GC-MS.
• Sensitivity: Direct detection of both polar and non-polar volatiles without derivatization or pre-concentration.
• Cost-effectiveness: Reduced analysis time and simplified workflow support routine quality control in packaging evaluation.

Future Trends and Potential Applications

Integration of MHE-SIFT-MS with advanced automation and data analytics is expected to further streamline VOC screening across diverse packaging materials. Potential extensions include real-time monitoring in production lines and broader application to polymer and ink analyses.

Conclusion

MHE-SIFT-MS offers a robust, rapid and quantitative solution for analyzing volatile compounds in paperboard, combining high throughput with broad compound coverage. Its implementation can enhance quality assurance processes in pharmaceutical and food packaging industries.

References

• P. Spanel, D. Smith (1996). Selected ion flow tube: a technique for quantitative trace gas analysis of air and breath. Med. Biol. Eng. Comput., 24, 409.
• D. Smith, P. Spanel (2005). Selected ion flow tube mass spectrometry (SIFT-MS) for on-line trace gas analysis. Mass Spec. Rev., 24, 661.
• B.J. Prince, D.B. Milligan, M.J. McEwan (2010). Application of SIFT-MS to real-time atmospheric monitoring. Rapid Commun. Mass Spectrom., 24, 1763.
• W. Shen, C. Wang (2012). Multiple headspace extraction for the quantitative determination of residual monomer and solvents in polystyrene pellets using the Agilent 7697A Headspace Sampler. Agilent Technologies Application Note.