Hi all,

We recently installed a Vario ISOTOPE Cube and overall it's running well. It's currently configured for CNS. I've been running our in-house standards to check the system out. Carbon values look fine and similar to what I was getting with the Eurovector. Sulfur is consistent, although I need to run some sulfur standards to confirm I'm getting close to the right values.

Nitrogen, though, is odd. The values for peptone, keratin and glycine are all 2-3 permil higher than expected and NIST 1547 and apple leaves are about 4-6 permil too heavy. It's like I've got an enriched N contamination. Other than a new EA, nothing else has changed in the system. If anyone has an idea or suggestions, I would really appreciate it!



Robert Michener
IRMS Laboratory Manager
Boston University Stable Isotope Laboratory
Department of Biology
5 Cummington Mall
Boston, MA  02215

Voice: 617-353-6980
Fax: 617-353-6340
Email: [log in to unmask]<mailto:[log in to unmask]>
"You are what you eat, plus a few permil!"