I am analyzing leachate samples from a soil column to which enriched N has been added. The leachate has been evaporated and the salt that remains is analyzed on a Finnigan Delta S for N15. The samples are highly enriched and I have been having problems with memory affects and a background build up that I think is due to halides. What can I do to minimize these problems? Is there an enrichment affect when the leachate is evaporated? If anybody has experience with a similar experimental design or running enriched samples please drop me a line.
National Soil Tilth Lab