Determination of N Abundance in Nanogram Pools of NO(3) and NO(2) by Denitrification Bioassay and Mass Spectrometry

Suspensions of two strains of Pseudomonas aeruginosa (ON12 and ON12-1) were used to reduce NO(3) and NO(2), respectively, to N(2)O. The evolved N(2)O was quantified by gas chromatography with electron capture detection, and the N abundance was determined by mass spectrometry with a special inlet sys...

Full description

Saved in:
Bibliographic Details
Published in:Applied and environmental microbiology 1994-07, Vol.60 (7), p.2467-2472
Main Authors: Højberg, O, Johansen, H S, Sørensen, J
Format: Article
Language:English
Subjects:
Bacteria
Biology
Nitrogen
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Suspensions of two strains of Pseudomonas aeruginosa (ON12 and ON12-1) were used to reduce NO(3) and NO(2), respectively, to N(2)O. The evolved N(2)O was quantified by gas chromatography with electron capture detection, and the N abundance was determined by mass spectrometry with a special inlet system and triple-collector detection. Sample gas containing unknown N(2)O pools as small as 0.5 ng of N was analyzed by use of a spike technique, in which a reference gas of N(2)O of natural N abundance was added to obtain enough total N for the mass spectrometer. In NO(3) or NO(2) pools, the N abundance could be determined in samples as small as approximately 3.5 ng of N. No cross-contamination took place between the NO(3) and NO(2) pools. The excellent separation of NO(3) and NO(2) pools, small sample size required, and low contamination risk during N(2)O analysis offer great advantages in isotope studies of inorganic N transformations by, e.g., nitrifying or denitrifying bacteria in the environment.
ISSN:0099-2240
1098-5336