HIGH-THROUGHPUT RESIDUAL SOLVENT AND RESIDUAL MONOMER ANALYSIS USING SELECTED ION FLOW TUBE MASS SPECTROMETRY

Significance of the Topic

Volatile organic solvent residues and monomer impurities in pharmaceutical formulations and food packaging materials pose safety, regulatory and organoleptic risks. Rapid, direct analysis techniques that eliminate time‐consuming sample preparation and chromatographic separation are essential to support high‐throughput quality assurance and process monitoring.

Aims and Overview of the Study

This study evaluates selected ion flow tube mass spectrometry (SIFT‐MS) combined with automated headspace sampling for fast quantification of residual solvents and monomers. Formaldehyde emissions from polyoxymethylene (POM) serve as a model system to demonstrate multicomponent screening and multiple headspace extraction (MHE).

Methodology

Samples were analyzed by direct headspace introduction into a Voice200ultra SIFT‐MS, using H3O+, NO+ and O2+ reagent ions for selective ion–molecule reactions. A GERSTEL MPS2 autosampler performed incubation, injection and vial flushing under software‐controlled PrepAhead scheduling. Analyses ran in Selected Ion Mode, with carrier gas helium and inlet temperature held at 150 °C.

Used Instrumentation

• Syft Technologies Voice200ultra SIFT‐MS
• GERSTEL MPS2 autosampler with septumless sampling head and agitator
• LabSyft Method Editor and GERSTEL Maestro software

Main Results and Discussion

Thirteen common residual solvents, including benzene and toluene, were quantified simultaneously in under 90 s by continuous ambient air sampling. Packaging monomers from polystyrene, POM and PET were screened in 60 s headspace scans. MHE analysis of formaldehyde from ground POM achieved a total headspace concentration of 13.8 ppmv (equivalent to 41 µg g–1) through three sequential injections and exponential decay fitting. Automation allowed 24 h operation and a 6.5-fold throughput increase over conventional GC methods.

Benefits and Practical Applications

Soft chemical ionization permits direct, real‐time quantification at ppt levels without preconcentration or derivatization. Rapid reagent‐ion switching enhances selectivity and resolves isobaric overlaps. The platform is readily deployed for pharmaceutical QA/QC, food safety assessment, environmental monitoring and inline process control.

Future Trends and Opportunities

Expansion of reagent ion libraries and integration with in‐line conveyor systems will extend applicability to broader volatile compound classes. Further automation of multiplexed headspace extraction and advanced software scheduling will boost throughput and quantitative precision.

Conclusion

Automated SIFT‐MS offers a versatile high‐throughput solution for residual solvent and monomer analysis, delivering rapid, sensitive and selective results without the complexity of chromatographic separation.

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