Analytical Solutions for Microplastics

Analytical Solutions for Microplastics: Practical Workflow, Techniques and Instrumentation

• Microplastics (<5 mm) are pervasive in aquatic and atmospheric environments and present ecological and potential human-health risks via ingestion, physical damage to organisms, and transfer/biomagnification of additives and sorbed contaminants (e.g., PCBs, PAHs, PFAS).
• Reliable monitoring and material identification are essential for risk assessment, regulatory harmonization and designing mitigation/recycling strategies.

• Present a comprehensive workflow and instrument solutions for microplastics (MPs) monitoring, from sampling and automated sample preparation to particle counting, size/shape analysis and material identification.
• Compare nondestructive spectroscopic (FTIR, IR/Raman, XRF) and destructive approaches (Py-GC-MS, DSC) and show how they complement each other for different size ranges and analysis goals.

• Sampling: surface water (ocean/river) sampling with nets (neuston nets) or grab sampling following local/ national guidelines.
• Automated pretreatment: MAP-100 automates common preparation steps — sieving, H2O2 digestion to remove organic matter, density separation (e.g., NaI) to remove heavy inorganic material, and filtration — reducing analyst hours, exposure risk and inter-operator variability. MAP-100 is optimized for particle long-diameter range ~0.3–5 mm (note: not suitable for very sandy/ muddy matrices that clog transport).
• Particle counting and morphological analysis: dynamic particle image analysis (iSpect DIA-10) for automated counting, size distribution (5–100 μm), shape and concentration (particles/mL), following ASTM D8489 procedures for 5–100 μm particles.
• Spectroscopic material ID and mapping: bench and microscopy FTIR (IRSpirit/IRTracer/IRXross with AIMsight/AIM-9000) and combined IR/Raman (AIRsight) provide nondestructive polymer ID and spatial maps for particles down to a few micrometers; specialized libraries (UV-damaged plastics library) improve matches for weathered plastics.
• Filter handling and high-throughput mapping: particle filter (PF) holder holds diverse filter types (PTFE, Al2O3, Au-coated PC, stainless steel) flat on microscope stage, enabling transmission/reflection measurements and high-speed mapping/particle-analysis software to accelerate imaging and spectral acquisition for MPs <100 μm.
• Destructive mass-based quantitation and identification: Pyrolysis-GC-MS (EGA/PY-3030D + GCMS) with F-Search MPs software enables qualitative and quantitative analysis of mixed and very small MPs (sub-100 μm) from a few mg of material, yielding mass fractions for multiple polymer types in heterogeneous environmental matrices (e.g., road shoulder debris, river extracts).
• Thermal methods for blended polymers: differential scanning calorimetry (DSC) can determine component ratios in mechanically blended polymers using heats of fusion and calibration curves; partial-area integration can be used when melting peaks overlap.
• Target contaminant analysis: GC-MS/MS (for PAHs) and LC-MS/MS (for PFAS) quantify toxic chemicals adsorbed onto MPs following solvent extraction (hexane for PAHs, methanol for PFAS) after an adsorption experiment.

• Automated preparation: MAP-100 Microplastic Automatic Preparation Device.
• FTIR bench systems: IRSpirit-X / IRSpirit-TX, IRTracer-100, IRXross; single-reflection ATR QATR-S / QATR-10; IR Pilot and Plastic Analyzer software; UV-Damaged Plastics Library.
• Infrared microscopes and accessories: AIMsight / AIM-9000, AIRsight (IR + Raman), PF holder (particle filter holder), high-speed mapping and particle analysis programs, wide-field camera and reflective objectives.
• Raman: AIRsight microscope with 785 nm excitation and high-magnification objectives (50x–100x).
• Particle image analysis: iSpect DIA-10 Dynamic Particle Image Analysis System.
• Elemental analysis: EDX-8000 / EDX-8100 X-ray fluorescence spectrometers for Cu and other elements.
• Pyrolysis GC-MS: EGA/PY-3030D (pyrolyzer) coupled to GCMS-QP2020 NX or GCMS-QP2050 and F-Search MPs software; UAMP column kits for pyrolysis separations.
• Cryogenic milling: IQ MILL-2070 for homogeneous grinding prior to Py-GC-MS quantitation.
• Thermal analysis: DSC-60 Plus series differential scanning calorimeter.
• Trace contaminant quantitation: GCMS-TQ8040 RX (GC-MS/MS) and LCMS-8060RX (LC-MS/MS) for PAHs and PFAS analysis.

• Automated MAP-100 preparation produced clean filterable residues from river samples; FTIR identification using the UV-damaged plastics library returned high match scores for weathered PP and PE particles (e.g., matches >870 points).
• High-speed infrared microscope mapping with PF holder enabled rapid identification and color-coded spatial maps of PE, PET and PS on 5 μm Si filters; particle analysis software quantified counts, size distributions and estimated volumes/masses (mass estimation based on empirical area–mass relationships; user caution recommended).
• AIRsight IR/Raman approach identified microplastics down to 5–10 μm (Raman) and ~10s μm by IR, enabling size-correlated chemical ID on the same stage without sample transfer.
• iSpect DIA-10 provided rapid particle counts and size/shape distributions for 5–100 μm fractions consistent with ASTM D8489; image thumbnails and scatterplots allow quality control of shredding or environmental samples.
• Py-GC-MS with MPs calibration standards achieved linear calibration (R2 ≥ 0.995) for a 12-polymer standard mix and enabled identification/quantitation of multiple polymer types in roadside debris (PE dominant, SBR from tire wear present); F-Search MPs allowed similarity scoring and mass% estimation without extensive isolation.
• Combined FTIR (number-based) and Py-GC-MS (mass-based) analyses of MAP-100-extracted river MPs showed complementary results: FTIR indicated particle counts dominated by PP (79.5% by count) while Py-GC-MS mass% was dominated by PE and PP with different mass proportions—highlighting number vs mass interpretation differences.
• Adsorption experiments quantified PAH and PFAS uptake on PP, PE and PS, showing polymer- and compound-specific adsorption tendencies (PAHs adsorbed more strongly to PP/PE in the reported experiments; PFAS adsorption varied by compound).

• Integrated workflows (automated preparation + high-throughput imaging + spectroscopy + pyrolysis) reduce analyst time, improve reproducibility and enable both number- and mass-based assessments required for regulatory and ecological context.
• Use of IR/Raman mapping and specialized libraries improves identification of weathered plastics common in environmental samples.
• Py-GC-MS provides robust mass-based quantitation for complex, mixed, and heavily degraded samples without the need for painstaking manual separation.
• Particle imaging systems support rapid screening and size/shape characterization needed for exposure/risk models and standardization efforts (ASTM, ISO inputs).

• Method harmonization: continued development of interlaboratory standards (ASTM D8489, WK87463 for spectroscopic ID) and shared libraries for weathered plastics will improve comparability of monitoring data.
• Automated end-to-end workflows combining pretreatment robots, AI-assisted spectral matching, and advanced image analysis will increase throughput and traceability for large monitoring programs.
• Improved mass estimation models or direct mass-measurement approaches for particles detected by imaging will help reconcile number-based and mass-based metrics used in policy and exposure assessment.
• Expansion of targeted contaminant analyses coupled with MPs (e.g., PFAS, legacy POPs, additives) will clarify the role of MPs in chemical transport and bioavailability in food webs.
• Development of minimally destructive methods and nanoscale characterization will be important as monitoring pushes below the micrometer range and for assessing internal sorbed contaminants.

• A suite of complementary analytical tools—automated pretreatment (MAP-100), imaging particle counters (iSpect DIA-10), IR/Raman microscopy (AIMsight/AIRsight), bench FTIR, Py-GC-MS, DSC and targeted MS/MS—provides an effective, practical workflow for robust microplastics monitoring and material/contaminant characterization across relevant size ranges.
• Choice of methods should be guided by the monitoring objective (particle counts and morphology versus mass-based polymer load versus adsorbed toxicants) and sample matrix; combining nondestructive and destructive techniques yields the most complete picture.

• T. Kataoka, Y. Iga, R. A. Baihaqi et al., Geometric relationship between the projected surface area and mass of a plastic particle. Water Research. 2024;261:122061.
• ASTM D8489, Test Method for Determination of Microplastics Particle and Fiber Size, Distribution, Shape, and Concentration in Waters with High to Low Suspended Solids Using a Dynamic Image Particle Size and Shape Analyzer. 2023.
• ASTM WK87463, New Test Method for Spectroscopic Identification and Quantification of Microplastic Particles in Water Using Infrared (IR) Spectroscopy (in development).
• ASTM D8402, Standard Practice for Development of Microplastic Reference Samples for Calibration and Proficiency Evaluation.
• Makoto Yasojima et al., Adsorption Characteristics of Chemical Substances on Microplastics, proceedings (Japan water environment symposia), 2019.
• Shimadzu Corporation, Analytical Solutions for Microplastics technical brochure, First Edition June 2020; © Shimadzu Corporation 2026 (document C10G-E083B).