Clarification of question 4.8: Does standard PyGCMS techniques used in the field today require > 1 microgram quantities for accurate polymer mass characterization in general?

Answer Explanations

• It depends (please explain)

  Expert 9
  As I have not used pyGCMS, I cannot provide informed comment.
• Yes

  Expert 3
  Below 1 µg, pyrolysis products may be too dilute to generate distinct chromatographic peaks, especially for complex polymers.
  
  
  
• Yes

  Expert 2
  In general, the standard Py-GC/MS techniques used in the field today require more than 1 µg of polymer material for accurate mass characterization. While there are modern instruments that are sensitive enough to sometimes detect and identify polymers from sub-microgram quantities, for having reliable and reproducible mass characterization typically requires multi-microgram sample sizes. This is because at very low amounts, the reproducibility, signal-to-noise ratio, and accuracy of quantification degrade making the results less dependable. Therefore, although trace-level detection is possible, accurate and routine polymer mass characterization by Py-GC/MS generally requires greater than 1 µg of sample.
• No

  Expert 7
  Py-GC/MS techniques do not require more than 1mg of polymer. From my experience, 10 ug is enough for analyzing polymers. 
  Searching result shows that modern techniques need even lower sample amount, only sub microgram. 
  
  
  
  
• It depends (please explain)

  Expert 4
  I actually am not sufficiently aware of the technical details of the PyGCMS technique to be able to reliably answer this question.
• No

  Expert 1
  PyGCMS methods have detection limits in the range of sub microgram quantities for majority of polymer types.  The instrument detection limits of PyGCMS are in the range of tens to hundreds of nanograms.  Those polymers with higher detection limits are a result of background levels of contamination from labware and plastics used in analytical method.  But the instrument itself can detection tens of nanograms to hundreds of nanogram levels (IDL).  
• No

  Expert 5
  New developments in spitless Py-GC/MS allow for detection in the low nanogram range.
  https://doi.org/10.1016/j.jaap.2022.105707
  https://doi.org/10.1021/acsestair.3c00035
  
  This is dependent on the polymer fragmentation pattern. PE and PP produces many fragments  of roughly equal abundance, thus mid nanogram range is possible. PMMA and PS produce fewer fragments with a few dominate in abundance, thus low nanogram range is possible with standard quadrupole MS. 
  MS/MS will enable lower than nanogram detection.
• It depends (please explain)

  Expert 6
  It depends on the instrument sensitivity and matrices complexity after clean-up procedure. In general, due to the above reasons, relative large amount > 1 micgrogram quantities is required to analyze the features of polymer pyrolyzates  for accurate polymer confirmation and mass characterization.  But with improved procedure or advancement of instrument, <1 microgram quantities are also possible for mass characterization. 
• It depends (please explain)

  Expert 8
  I'm not sure there are standard pyGCMS techniques today.  We are all still trying to figure out the best way forward. If by "standard" you mean a calibration curve that's created at a microanalytical balance, then yes. The detection limit is limited by the lab's microanalytical balance which is typically 0.0000001 g (0.1 ug) resolution. Since the last digit isn't significant on a balance, the lowest mass of measurable amount is 1 ug placed in the lowest cal cup. Hence the bottom of the calibration curve.  However, solvent extraction methods allow for the dilution of a weighed quantity of polymer to lower concentrations than can be measured at the balance. These methods have promising capabilities to reduce the quantification method - yet the detection limit is still dependent upon reducing matrix interference and background contamination.