Microplastics Analysis using Micro-Furnace Pyrolyzer and F-Search MPs Software

Importance of Topic

Microplastics (MPs) are persistent plastic fragments (<5 mm) originating from degradation or direct manufacture. They accumulate ubiquitously, threatening ecosystems, food chains, and human health. Reliable identification and quantification of MPs are essential for environmental monitoring, risk assessment, and remediation strategies.

Objectives and Study Overview

This whitepaper describes the development and application of Pyrolysis–Gas Chromatography/Mass Spectrometry (Py-GC/MS) methods and F-Search MPs software for standardized, high-throughput microplastic analysis. Key goals include creation of calibration standards, enhancement of measurement sensitivity via F-Splitless injection, and demonstration across diverse sample types: environmental dust, marine and sediment samples, and waste plastics.

Methodology and Instrumentation

The analytical workflow comprises sampling, pretreatment, automated pyrolysis, GC/MS separation, and software-guided data processing. Instrumentation:

• Multi-Mode Micro-Furnace Pyrolyzer (vertical furnace, ±0.1 °C control)
• Auto-Shot Sampler (48-position automated sampling)
• MultiJet Cryo-Trap for focused cryo-trapping
• Multi-Functional Splitless Sampler enabling F-Splitless injection
• GC/MS with UA-5 and UAMP columns
• F-Search MPs software for automated peak recognition, calibration, and quantification

Main Results and Discussion

• Calibration standards using inert diluents (SiO₂, CaCO₃) achieved linear quantification (R² > 0.99) for 11–12 polymers with LODs down to ~0.03 µg.
• CaCO₃-diluted standards prevented hydrolysis and catalytic conversion of reactive pyrolyzates (e.g., PU detection as MDA).
• F-Splitless injection improved signal intensities up to 48-fold and lowered polystyrene LODs to pg levels; SIM mode reached LOD ~ 17 pg.
• Applications:
  • Tire and road wear MPs in road dust: 22.6 mg/kg (industrial) vs. 9.8 mg/kg (residential).
  • Marine surface MPs (Osaka Bay): identification of PS, PE, PP by characteristic pyrolyzates.
  • Beach plastic wastes: TD–GC/MS profiling of additives; Py-GC/MS pyrolyzate fingerprints.
  • Multilayer packaging waste: TD–GC/MS detection of plasticizers; catalytic pyrolysis yielded BTEX with zeolite catalysts.
  • Sediment samples: F-Splitless Py-GC/MS quantified MPs in seafloor sediments (PE dominant, plus PP, PS, PMMA, PET, nylon).

Benefits and Practical Applications

The integrated Py-GC/MS and F-Search MPs approach enables rapid, reproducible screening of complex matrices, minimal sample preparation, high sensitivity for trace MPs, and automated data processing—valuable for environmental monitoring, regulatory compliance, QA/QC, and research.

Future Trends and Potential Uses

Emerging directions include:

• Portable, field-deployable pyrolysis systems for in-situ monitoring
• High-resolution mass spectrometry for detailed polymer fingerprinting
• Machine learning algorithms for spectral deconvolution of mixed plastics
• Expanded polymer and additive libraries to cover novel materials
• Integration of imaging and spectroscopy for particle morphology and composition
• Eco-friendly sample pretreatment and catalytic upcycling of plastic wastes

Conclusion

The described micro-furnace Py-GC/MS methods, complemented by F-Search MPs software and F-Splitless injection, deliver a robust, sensitive, and standardized protocol for comprehensive microplastic analysis across diverse environmental and waste samples.

Reference

1. M. Matsueda et al., J. Anal. Appl. Pyrolysis 154 (2021) 104993.
2. T. Ishimura et al., J. Anal. Appl. Pyrolysis 157 (2021) 105188.
3. K. Tei et al., J. Anal. Appl. Pyrolysis 168 (2022) 105707.
4. M. Z. Siddiqui et al., Sci. Total Environ. 784 (2021) 147177.