Are there best practices for minimizing/eliminating analyte-like response in procedural blanks?

Answer Explanations

• Yes (please explain)

  Expert 3
  This requires targeted QA/QC strategies, such as blank characterization (FTIR, Raman...), double verification (dual methods, whenever possible). These contribute to ensure that microplastics are true positives, and not artifacts of contamination or misidentification.
• No

  Expert 9
  I think this is an area that is currently under explored. Development of open access spectral libraries of MNP-free matrices, derived from analysis of archived historical MNP-free biological tissues would be one avenue to explore to minimise matrix effects.
• Yes (please explain)

  Expert 2
  Yes, there are several practices  that could be used in order to  minimize or eliminate the analyte-like responses in procedural blanks. One of the most important step is to ensure the accuracy and integrity of the trace-level analytical work such as environmental testing, food safety, or pharmaceutical analysis. Procedural or method blanks normally should not  contain any detectable analyte. For this to be accurate  it is essential to use high-purity reagents and solvents that are known to be contaminant free and were previously  properly filtered. More than that all the reagents used need to be ultra-pure or distilled, especially for trace metals analysis. For a better changes in the minimizing and elimination of analyte like response, all the labware should be thoroughly cleaned, due to the fact that both glassware and plasticware can leach or adsorb analytes. This could be done using  acid washing , thorough rinsing with ultra-pure water, and, when possible, using dedicated or certified clean containers, particularly for ultra-trace work. Another important aspect is the ability to control the sample preparation environment. For this purpose, clean benches or laminar flow hoods should be used. Also, the airborne contamination needs to be monitored properly, and the personnel that works in the lab should wear powder-free gloves and try to avoid personal care products containing potential analytes. The procedural blanks should be run alongside samples and include solvent blanks, reagent blanks, and instrument blanks to identify contamination sources throughout the workflow.  Also, the ongoing monitoring of potential sources of laboratory contamination is also very important. This could be performed by assessing the quality of the lab air, which may carry  either phthalates or hydrocarbons; plastic components such as tubing and seals, which can leach DEHP or BPA; as well as cleaning agents and gloves.
• No

  Expert 4
  I am not aware of such practices.
• Yes (please explain)

  Expert 1
  Pyrolysis GCMS methods may not have issues related to analyte-like responses in procedural blanks.  My suggestion would be to perform two different methods of analysis (complementary methods) to confirm your results.  
• Yes (please explain)

  Expert 5
  For Optical spectroscopy, treat  your sample as a sterile sample, going to great lengths to avoid any contamination.
  For PY-GC/MS, non-polymeric material can be eliminated with a thermal extraction step before pyrolysis. Usually thermally extracting at 280 °C - 300 °C eliminates natural contaminants such as limonene, benzene, naphthalene, long chain organic acids/amides, etc.
• Yes (please explain)

  Expert 6
  To minimizing/eliminating analyte-like response in procedural blank, one should consider using procedural equipment, device, and consumables that are material-wise different from analyte. Sometimes it is difficult as plastics due it inner, cheat, safe, and stable features has been widely used in lab settings.  
• No

  Expert 8
  This shouldnt be minimized.  The blanks should reflect what the samples experienced without trying to eliminate contamination in the blank.
• Yes (please explain)

  Expert 7
  There are different things that can be done to minimize/eliminate analyte-like response in procedural blanks, for example, using high-purity reagents and solvents, thoroughly cleaning labware, using specific gloves, minimizing environmental contamination, running instrumental blanks...