Abstract
The automated Dumas technique described by Barsdate and Dugdale for quantitative determination of total organic nitrogen and isotope enrichment in marine phytoplankton has been refined. The method involves manometric and mass spectrometric measurements for total nitrogen and nitrogen isotopes, respectively. Expressions for calculating isotope enrichment have been derived and include temperature, background, and ion pump corrections. The latter can be a major source of error in atom-percent enrichment calculations when ion pumps are used to maintain very low background pressures in the analyzer chamber. When such systems are adopted for 15N tracer analysis, calibration curves should be established prior to analysis to assess the level of interference.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
