Dear Ran Tal

PP will not stand conc. HNO3 for very long. Unfortunately there are not many alternatives over PTFE or PFA (probably even more expensive but better to clean for ICPMS work). Quartz is sure an alternative too, but the blank can be high for certain elements. If you do ICPMS analyses, you will certainly dilute the digest at least ten times before analysis, which in my experience is OK with PP. My suggestion would be to use Quartz if your application can afford the blanks and PFA or similar for the digestion and re-use the digestion vials after thorough cleaning.

Hope this helps

Bodo

Are your microwave digestion vessels actually made of PP, or are you transferring to PP after digestion? Most Microwave digestion systems use PTFE or PFA vessels with a rigid sleeve, to help the vessel maintain it's shape. If you are transferring solutions to PP or PE bottles and then diluting them, that should be fine.

thank you guys, it was very helpful. Indeed the microwave vessels are PTFE and I'm transferring to PP tubes. thanks !