Rapid analysis of additives in food packaging

Significance of the Topic

The presence of additives such as plasticizers in food packaging can lead to migration into food products, posing health and regulatory concerns. Rapid, reliable identification of these compounds is essential for consumer safety and compliance. The direct analysis approach using ASAP coupled with single quadrupole mass spectrometry reduces sample preparation time and simplifies workflows.

Objectives and Study Overview

This study aimed to develop and evaluate a rapid screening method for extractables in food wrappers by combining atmospheric pressure solid analysis probe ionization with an Agilent 6120 Single Quadrupole MS and MassWorks calibration software. The specific objectives were to:

• Introduce samples directly without chromatographic separation
• Calibrate quadrupole MS data to achieve accurate mass measurements
• Determine elemental compositions of unknown additives via database searching

Methodology and Instrumentation

The workflow comprised the following steps:

• Extraction of 300 mg of packaging material in 5 mL tetrahydrofuran (THF)
• Application of the THF extract onto a glass capillary and insertion into the ASAP probe
• Thermal vaporization by heated nitrogen and ionization via atmospheric pressure chemical ionization (APCI)
• Introduction of a vitamin D3 standard (100 ng/µL) at 50 µL/min for post-acquisition calibration
• Accurate mass calibration and elemental composition analysis using MassWorks and its CLIPS algorithm

Instrumentation Used

• Agilent 6120 Single Quadrupole Mass Spectrometer with an ASAP ionization source (IonSense)
• Syringe pump for continuous infusion of calibration standard
• Cerno MassWorks software with Calibrated Lineshape Isotope Profile Search (CLIPS)

Main Results and Discussion

After rapid introduction of the THF extract, MassWorks calibration improved mass accuracy sufficiently to detect an ion at m/z 403.2463. CLIPS analysis assigned this signal to C20H35O8+ with 99.5% spectral accuracy. A database search on ChemSpider matched the composition to acetyl tributyl citrate, a common plasticizer. This approach demonstrated that a single quadrupole system, when calibrated post-acquisition, can reliably determine elemental compositions and distinguish among candidate formulas based on spectral accuracy.

Advantages and Practical Applications

• Rapid turnaround: analysis and calibration completed within minutes
• Simplified workflow: eliminates the need for liquid chromatography
• Cost-effective: uses accessible single quadrupole instrumentation
• High confidence identification: accurate mass determination via post-processing calibration

Future Trends and Potential Applications

The integration of accurate mass calibration workflows with routine quadrupole MS is likely to expand into environmental monitoring, pharmaceutical impurity profiling, and polymer additive analysis. Future developments may involve automated sample introduction, expanded calibration standards, and direct integration with compound identification databases to enable high-throughput screening.

Conclusion

The combination of ASAP ionization, single quadrupole mass spectrometry, and MassWorks software provides a fast, reliable, and cost-effective strategy for detecting additives in food packaging without the need for chromatographic separation. This workflow enhances routine screening capabilities in food safety and other application areas.

References

No formal literature references were provided in the original document.