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Title: A simple method for the quantification of amidic bioavailable dissolved organic nitrogen in seawater
Abstract A targeted method for the quantification of bioavailable amide N found in marine DON (bDON) is presented. The method utilizes mild acid hydrolysis to convert amide N found in proteins andN‐acetyl amino polysaccharides to primary amine containing products that are measured using a highly sensitive (nanomolar range and precision) fluorometric technique with addition ofO‐phthaldialdehyde. We find amidic bDON concentrations ranging from 0.08 to 1.82 μM N within waters from the upper 300 m in the southern California Current, Southern California Bight, and subtropical North Pacific representing 15–33% of bulk DON concentrations. Bioassay experiments from the North Pacific revealed consumption of ~20% of the in situ bDON within 5 days. The method represents a simple and rapid tool for the quantification of bioavailable DON concentrations in seawater with improved analytical precision over traditional estimates of bulk DON concentrations.  more » « less
Award ID(s):
2224726 2241005
PAR ID:
10518143
Author(s) / Creator(s):
;
Publisher / Repository:
ASLO
Date Published:
Journal Name:
Limnology and Oceanography: Methods
ISSN:
1541-5856
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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