Residual Solvents Analysis from Flexible Packaging Materialusing Brevis GC-2050

Significance of the Topic

The presence of residual organic solvents in flexible packaging materials poses safety and regulatory risks, especially in food contact applications. Accurate quantification of volatile residues is critical to ensure consumer protection, compliance with hygiene standards and process quality control in packaging production.

Objectives and Study Overview

This study demonstrates a workflow for headspace gas chromatography analysis of 21 common residual solvents extracted from solid flexible packaging samples. Key aims include:

• Establishing reliable calibration curves for target solvents.
• Validating system repeatability at low concentration levels.
• Quantifying solvent emissions from different film materials.

Methodology and Instrumentation

Solid packaging samples were introduced into 20 mL vials and equilibrated at 80 °C for 30 min in a headspace sampler. Vapor-phase aliquots (1 mL) were transferred to the GC system using nitrogen as carrier gas. Quantification relied on external standard calibration with four concentration levels of mixed solvent solution.

Used Instrumentation

• Gas chromatograph: Shimadzu Brevis GC-2050
• Headspace sampler: Shimadzu HS-20 NX (loop mode)
• Column: SH-WAX, 60 m × 0.25 mm I.D., 0.25 µm film
• Carrier gas: Nitrogen, constant linear velocity (25 cm/s)
• Detector: FID (H₂ flow 32 mL/min, air 200 mL/min, makeup N₂ 24 mL/min)

Main Results and Discussion

Calibration of 21 solvents achieved excellent linearity (R² > 0.998) over the range 1.96–19.6 mg/m². Repeatability at the lowest calibration level showed relative standard deviations below 3% (n=3) for all analytes. Analysis of five packaging materials (A–E) revealed variable residual levels:

• Acetone: 0.003–0.017 mg/m²
• Ethyl acetate: up to 0.056 mg/m²
• Methanol: 0.005–0.319 mg/m²
• Iso-propanol: 0.008–0.107 mg/m²
• Other solvents (toluene, styrene, MEK) detected at trace levels.

Chromatograms showed clear separation of all compounds without interference from matrix components. The nitrogen carrier gas provided stable baseline and reliable quantification.

Benefits and Practical Applications

• Compact GC footprint minimizes laboratory space requirements.
• Fully automated headspace sampling streamlines sample throughput.
• Use of nitrogen reduces operational costs and logistical constraints.
• Method supports routine quality control of food and pharmaceutical packaging.

Future Trends and Opportunities

Advancements may include integration of ultra-fast GC columns for shorter analysis times, coupling with mass spectrometry for enhanced specificity, development of automated compliance reporting tools, and adoption of greener carrier gases or solvent-free extraction techniques. Data analytics and machine learning are likely to play a growing role in trend monitoring and predictive maintenance of instrumentation.

Conclusion

The combined HS-20 NX/Brevis GC-2050 system delivers robust, precise and space-efficient analysis of residual solvents in flexible packaging materials. Calibration performance and repeatability meet stringent QC requirements, and application data demonstrate its suitability for routine monitoring in manufacturing and regulatory environments.

References

Manual for Handling Instruments with Manufacturing of Flexible Packaging Materials, 6th Edition, October 2017, Flexible Packaging Hygiene Association.