eCite Digital Repository

Development and initial deployments of an autonomous in situ instrument for long-term monitoring of copper (II) in the marine environment

Citation

Holm, CE and Chase, Z and Jannasch, HW and Johnson, KS, Development and initial deployments of an autonomous in situ instrument for long-term monitoring of copper (II) in the marine environment, Limnology and Oceanography: Methods, 6, (July) pp. 336-346. ISSN 1541-5856 (2008) [Refereed Article]


Preview
PDF
Restricted - Request a copy
3Mb
  

Copyright Statement

Copyright 2008 the American Society of Limnology and Oceanography, Inc

Official URL: http://www.aslo.org/lomethods/free/2008/index.html

DOI: doi:10.4319/lom.2008.6.336

Abstract

We developed an autonomous, in situ instrument to detect dissolved copper in seawater, suitable for deployment on time scales from weeks to a month. A commercially available in situ nitrate analyzer (YSI 9600) was adapted to measure copper (II) by chemiluminescence. Modifications included construction of a photomultiplier (PMT)–based detector and flow-cell, the use of more chemically resistant plastics for parts in contact with the reagents, addition of an online acidification step, and optimization of the method and flow parameters. Microsolenoid pumps take in sample and dispense reagent, standard, and blank solutions, which are stored in 1 L plastic bags. Filtration (0.45 ìm) and acidification (pH ~1.7) permit a measurement of total dissolved Cu(II). Calibration is achieved by periodically analyzing ligand-stabilized seawater standard and blank solutions stored at pH 8 and acidified online. Averaged over all in situ deployments, the instrument had a detection limit of 0.8 ± 0.3 nM, a sample precision of 11% (n = 612), and an accuracy of 17% (compared to discrete samples n = 27). The instrument is capable of functioning autonomously for 25 d when sampling every hour and calibrating every 6 h. Reagent consumption is the limiting factor.

Item Details

Item Type:Refereed Article
Keywords:copper marine systems sensor
Research Division:Earth Sciences
Research Group:Oceanography
Research Field:Chemical Oceanography
Objective Division:Expanding Knowledge
Objective Group:Expanding Knowledge
Objective Field:Expanding Knowledge in the Earth Sciences
Author:Chase, Z (Associate Professor Zanna Chase)
ID Code:79530
Year Published:2008
Deposited By:IMAS Research and Education Centre
Deposited On:2012-09-18
Last Modified:2012-11-06
Downloads:0

Repository Staff Only: item control page