+ Site Statistics
References:
52,654,530
Abstracts:
29,560,856
PMIDs:
28,072,755
+ Search Articles
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ PDF Full Text
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn

+ Translate
+ Recently Requested

Application of a superoxide (O(2)(-)) thermal source (SOTS-1) for the determination and calibration of O(2)(-) fluxes in seawater



Application of a superoxide (O(2)(-)) thermal source (SOTS-1) for the determination and calibration of O(2)(-) fluxes in seawater



Analytica Chimica Acta 667(1-2): 1-13



Superoxide (O(2)(-)) is an important short lived transient reactive oxygen species (ROS) in seawater. The main source of O(2)(-) in the ocean is believed to be through photochemical reactions though biological processes may also be important. Sink terms for O(2)(-) include redox reactions with bioactive trace metals, including Cu and Fe, and to a lesser extent dissolved organic matter (DOM). Information on the source fluxes, sinks and concentration of superoxide in the open ocean are crucial to improving our understanding of the biogeochemical cycling of redox active species. As O(2)(-) is a highly reactive transient species present at low concentrations it is not a trivial task to make accurate and precise measurements in seawater. In this study we developed the appropriate numerical analysis tools and investigated a number of superoxide sources and methods for the purposes of calibrating O(2)(-) concentrations and/or fluxes specifically in seawater. We found the superoxide thermal source bis(4-carboxybenzyl)hyponitrite (SOTS)-1 easy to employ as a reliable source of O(2)(-) which could be successfully applied in seawater. The thermal decomposition of SOTS-1 in seawater was evaluated over a range of seawater temperatures using both a flux based detection scheme developed using two spectrophotometric methods: (i) 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) and (ii) ferricytochrome c (FC), or a concentration based detection scheme using a chemiluminescence flow injection method based on the Cypridina luciferin analog 2-methyl-6-(p-methoxyphenyl)3-7-dihydroimidazol[1,2-alpha]pyrazin-3-one (MCLA) as reagent. Our results suggest SOTS-1 is the best available O(2)(-) source for determining concentrations and fluxes, all detection systems tested have their pros and cons and the choice of which to use depends more on the duration and type of experiment that is required.

(PDF emailed within 0-6 h: $19.90)

Accession: 051607744

Download citation: RISBibTeXText

PMID: 20441861

DOI: 10.1016/j.aca.2010.03.054



Related references

Calibration of a chalcogenide glass membrane ion-selective electrode for the determination of free Fe super 3+ in seawater; I, Measurements in UV photooxidised seawater. Marine Chemistry 68(4): 283-294, 2000

Neutron survey meter calibration with a plutonium 239 beryllium source a computer assisted approach to calibration factor determination. Health Physics 56(SUPPL 1): S24, 1989

Determination of copper complexation with natural organic ligands in seawater by equilibration with MnO (sub 2) ; II, Experimental procedures and application to surface seawater. Marine Chemistry 11(4): 323-342, 1982

Determination of copper complexation with natural organic ligands in seawater by equilibration with MnO2. II. Experimental procedures and application to surface seawater Algae. 1982

Linear calibration using a single calibration standard and bayesian method application to azidothymidine determination. Analytica Chimica Acta 260(1): 83-91, 1992

Ultra-trace plutonium determination in small volume seawater by sector field inductively coupled plasma mass spectrometry with application to Fukushima seawater samples. Journal of Chromatography. A 1337: 171-178, 2014

Determination of superoxide in seawater using 2-methyl-6- -3,7-dihydroimidazo pyrazin-3 -one chemiluminescence. Analytical Chemistry (washington): 4, 1215-1227, 2008

A Cenozoic seawater Sr/ Ca record from benthic foraminiferal calcite and its application in determining global weathering fluxes. Earth and Planetary Science Letters 208(1-2): 69-84, 2003

Determination of superoxide in seawater using 2-methyl-6-(4-methoxyphenyl)-3,7- dihydroimidazo[1,2-a]pyrazin-3(7H)-one chemiluminescence. Analytical Chemistry 80(4): 1215-1227, 2008

A flash-photometric method for determination of reactivity of superoxide: application to superoxide dismutase assay. Journal of Biochemistry 91(3): 889-896, 1982

Electrolytic calibration technique for dissolved nitrogen determination in seawater by on-stream stripping gas chromatography. Analytical Chemistry 44(4): 885-887, 1972

Application of short controlled drop time polarography to the study of superoxide ion dismutation in aqueous solutions determination of the activity of superoxide dismutases. Bioelectrochemistry & Bioenergetics 13(4-6): 385-392, 1985

Application of seawater source heat pump. Journal of the Energy Institute 82(2): 76-81, 2009

A two-source approach for estimating turbulent fluxes using multiple angle thermal infrared observations. Water resources research 33(6): 1495-1508, 1997

Determination of source-rock thermal maturity by direct measurements and predictive modeling; application to Upper Cretaceous Cody Shale, Powder River basin, Wyoming. Pages 167-175 1990, 1990