6.5
SciPi 770: Best Practices: Detecting and Quantifying Micro- Nanoplastics (MNP) in Biological Tissues
What is the state of compatibility of analytical methodology between approaches that examine physical characteristics and chemical characteristics of MPs?
Results
(9 Answers)
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Expert 9
While there is still room for improvement (and such improvements will inevitably ensue), I would say that these two approaches are reasonably compatible at the current time. -
Expert 3
This compatibility is very limited, but, in terms of instrumentation, is improving, as evidenced by combined imaging and spectroscopic methods (e.g., uFTIR and uRaman). -
Expert 4
The compatibility between analytical approaches that target the physical and chemical characteristics of MNPs is improving, but it still faces critical limitations—especially when analyzing complex samples or smaller particles (<20 µm). Optical microscopy, SEM, AFM, flow cytometry, as techniques for physical characterization, are for instance partially compatible (as it depends on the integration or correlation methods available) with FTIR, Raman, Py-GC/MS, μFTIR, μRaman as available for chemical characterization. A challenge is that some methods (like Py-GC/MS) are destructive and do not allow to trace which particles had a specific size or shape. There is also the issue of potential loss of particles upon transfer from one technique to another, on top of possible misalignment and cross-contamination. -
Expert 2
There are some techniques that might be compatible for the examination of both physical and chemical characteristics of microplastics. The sample preparation usually starts similarly for many methods (the sample preparation including digestion of organic matter, density separation, filtration is recommended and utilized for both physical and chemical analysis). There are some techniques such as μFTIR and Raman spectroscopy that could allow the obtaining of both physical (e.g., size, shape) and chemical information about the samples. Also, the Py-GC/M analysis which is usually used for chemical identification, due to the fact that it destroys the sample it could be used to sort or sieve by size. Additionally there are some integrated methods combining image analysis with spectroscopy that can allow both image particle detection as well as a chemical mapping of the sample. -
Expert 1
Very little is done to compare FTIR/Raman with GCMS methods in the analysis of MNPs. It is because the former technologies are mostly used in physical chemistry labs while the latter is used in organic chemistry labs. It is important that scientists in different fields communicate to develop a reliable and reproducible method to measure MNPs in biological samples. -
Expert 5
Trying to use morphology and polymer density is still suspect in its accuracy.
Comparison of pyrolysis gas chromatography/mass spectrometry and hyperspectral FTIR imaging spectroscopy for the analysis of microplastics | Analytical and Bioanalytical Chemistry (https://doi.org/10.1007/s00216-020-02979-w) -
Expert 8
Some are compatible, some are not. Two methods or more are necessary for a lot of certainty. -
Expert 6
LDIR is the methodology that can do image and measure size (physical characteristics) and chemical properties by IR. -
Expert 7
Physical characterization methods which characterize the size, shape, color and morphology of MPs and Chemical Characterization Methods which study the compositions of MPs provide different information of MPs.
The compatibility between analytical methods for examining physical and chemical characteristics of microplastics (MPs) shows mixed consensus among experts. Several experts indicate that compatibility is currently limited but improving, with Expert 3 describing it as "very limited" and Expert 4 noting it "faces critical limitations" especially for smaller particles.
Some experts highlight promising integrated approaches, with Expert 2 and Expert 6 pointing to specific techniques that can analyze both aspects simultaneously:
- μFTIR and Raman spectroscopy (Expert 2)
- LDIR methodology (Expert 6)
- Combined imaging and spectroscopic methods (Expert 3)
However, challenges remain, including potential sample destruction with some methods (Expert 4), limited cross-field collaboration (Expert 1), and questionable accuracy when using morphology and polymer density (Expert 5). Expert 8 succinctly notes that "two methods or more are necessary for a lot of certainty."
Summary Generated by AI
Expert 4
07/31/2025 05:56Expert 2
07/31/2025 07:29Expert 5
08/01/2025 08:55