Read The Question first…
Let’s review…we soaked small pieces of different gloves in acetonitrile for 30 minutes. The samples were tested using GC-TOFMS. For relative intensity, a dashed line at the peak height of a 2 ppm PAH standard is drawn on the chromatograms.
Which gloves produced the worst background? GREEN GLOVES
Bright green, yellow latex and royal blue gloves had similar background levels even though the chromatograms look different. Baby blue gloves and green gloves had higher background. Green gloves had the highest intensity background peaks. Let’s look at the data…
I have to admit that I was a bit surprised at the answer to the next question. Several people emailed me answers and UV stabilizers was the most popular choice. However, we saw several antioxidant compounds in the glove samples. A couple of compounds are shown below. Check out the signal from antioxidant “Nocrack NS 6” in the baby blue gloves!
Antioxidants are added to rubber to prevent oxidative damage that degrade the physical and mechanical properties of rubber materials.
Thanks for these blog posts to reflect on the potential sources of ghost peaks in our GC chromatograms. Adding to these, we regularly see ghost peaks originating from plastic consumables or sample containers, where additives and/or a wax fraction leach into the solvent. We’re using glassware as much as possible but when samples arrive in plastic containers without blank material in a similar container one needs to be aware of that.
Thank you for your comment Ward.
We also use glass most of the time. Avoiding plastic in lab is especially important when using solvents that are stronger than acetonitrile.