If you havenít done so in the meantime already, may I suggest you contact Arndt Schimmelmann at Indiana Uni? What he doesnít know about flame-sealing ampules without causing isotopic fractionation to their contents is not worth knowing.
Prof. Dr W Meier-Augenstein, CChem, FRSC
Stable Isotope Forensics & Analytical Sciences
Robert Gordon University
School of Pharmacy and Life Sciences
The Ian Wood Building
E-mail: [log in to unmask]
From: Stable Isotope Geochemistry <[log in to unmask]> on behalf of mwolhowe . <[log in to unmask]>
Sent: 11 July 2019 20:37:26
To: [log in to unmask]
Subject: [ISOGEOCHEM] Derivitization Reagent Prep Advice?
Hey all. Not exactly an 'isotope geochem' question but the sort of thing multiple people on here who do compound-specific work might deal with. I've got to ampulize a bunch of pyridine and acetic anhydride for alcohol derivitizations. I need to A) have them not blow up on me while I'm flame sealing and B) not let the acetic anhydride evaporate at all while I'm doing it (as it will be characterized for IRMS work). I know the way to do this is with an ice bath to keep the vapor pressure down, but I also need to keep both of them extremely dry.
I figure the only way I'm going to be able to do this is to take the ampules ONE AT A TIME, fill them, stick a gentle nitrogen stream into the top, ice bath for a few seconds with the nitrogen needle in, then seal. If I try to do these in batches they'll either be getting evaporated by the nitrogen stream or collecting moisture while sitting there as I work my way down the line, I think.
Does this seem reasonable? Anyone got a better method for doing dry, non-evaporating, flame sealing of flammable stuff in bulk? Or am I just going to be at this for days?
University of Washington
School of Oceanography
Robert Gordon University has been awarded a TEF Gold award for the quality of its undergraduate teaching and learning, placing it in the top 20% of Universities in the UK
Robert Gordon University, a Scottish charity registered under charity number SC 013781.
This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary material, confidential information and/or be subject to legal privilege. It should not be copied, disclosed to, retained or used by, any other party. If you are not an intended recipient then please promptly delete this e-mail and any attachment and all copies and inform the sender. Please note that any views or opinions presented in this email are solely those of the author and do not necessarily represent those of Robert Gordon University. Thank you.