Dissolved Cd, Co, Cu, Ni, Mn and Pb along the CLIVAR I8S/I9N Indian Ocean transects Peter Morton 1 , Angela Milne 2 , William Landing 1 , Chris Measures 3 , Cliﬅon Buck 1 , Kathleen Gosnell 4 , Maxime Grand 3 , Mariko Hatta 3 , and William Hiscock 3 1 Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, Florida, USA 2 School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK 3 Department of Oceanography, University of Hawaii-Manoa, Oahu, Hawaii, USA 4 Department of Marine Sciences, University of Connecticut, Groton, Connecticut, USA Project Overview Automated Trace Metal Extraction Building on the method developed by Milne et al. 2010 2 , we have automated much of the time-consuming process of extracting and preconcentrating trace metals from seawater. References 1 C.I. Measures, W.M. Landing, M.T. Brown, C.S. Buck, Limnol. Oceanogr.-Meth., 6 (2008) 384. 2 A. Milne, W.M. Landing, M. Bizimis, P.L. Morton, Anal. Chim. Acta, 665 (2010) 200. February-April 2007 Samples collected using CLIVAR trace metal rosette 1 Twelve 12-L GO-Flo bottles 80 stations, 12 depths per station 1000 dissolved trace metal samples Collected into acid-washed 125 mL LDPE bottles Acidified to 0.024 M HCl (using 6 M quartz distilled HCl) To explore the biogeochemistry of dissolved trace metals in the Indian Ocean, from the Bay of Bengal to the Antarctic margin Region of Study Sample collection Preparing the CLIVAR trace metal rosette for deployment Sample analysis Dissolved Fe and Al measured shipboard by Grand, Hatta, and Measures (data not shown) Dissolved Cd, Co, Cu, Mn, Ni, and Pb measured at Florida State University y = 89355x + 87731 R² = 0.9995 y = 96802x + 16288 R² = 0.9998 y = 91268x + 650 R² = 0.9982 y = 110203x + 214024 R² = 0.9994 y = 79737x + 31617 R² = 0.9982 y = 89609x + 43790 R² = 0.9996 0 50000 100000 150000 200000 250000 300000 350000 0.0 0.2 0.4 0.6 0.8 1.0 Counts per second Mn (nmol/kg) Mn Standard Addition slopes Results, to date Contoured trace metal data are shown with overlays of related physical parameters. OCE 0649639 Method highlights 40x sample preconcentration (20 mL into 0.5 mL) Streamlined UV-oxidation (minimal sample transfer) Automated sample uptake and elution Online buffering to pH 5.8-6.2 (ammonium acetate, 0.4 M) Six hours to extract 24 samples System components Nobias Chelate PA-1 chelating resin (polycarbonate column) Cetac ASX-500 Autosampler (sample uptake) Cetac ASX-100 Autosampler (fraction collector) Dynamax Rainin RP-1 peristaltic pumps Vici 10-port injection (2 position) valve All components coordinated with FloZF v5.0 (GlobalFIA) Extraction sequence Precondition system with UV trace metal-free seawater Sample uptake: 10 minute 2 mL/min flow rate Rinse: 1 mL UHP water (18 Mohm-cm) Elution: 0.5 mL 1.0 M HNO 3 (QD or Optima) Wash: 1 mL 1.0 M HNO 3 (QD or Optima) Conditioning: 4 mL 0.08 M NH 4 -acetate Quantification ermo ELEMENT 2 HR-ICP-MS Isotope dilution: Cd, Cu, Ni and Pb Standard additions: Co and Mn Certified against SAFe S, D1 and D2 Similar slopes indicate consistent buffering throughout extraction

Dissolved Cd, Co, Cu, Ni, Mn and Pb along the CLIVAR I8S ... · Dissolved Cd, Co, Cu, Ni, Mn and Pb along the CLIVAR I8S/I9N Indian Ocean transects Peter Morton1, Angela Milne2, William

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Page 1: Dissolved Cd, Co, Cu, Ni, Mn and Pb along the CLIVAR I8S ... · Dissolved Cd, Co, Cu, Ni, Mn and Pb along the CLIVAR I8S/I9N Indian Ocean transects Peter Morton1, Angela Milne2, William

Dissolved Cd, Co, Cu, Ni, Mn and Pb along the CLIVAR I8S/I9N Indian Ocean transectsPeter Morton1, Angela Milne2, William Landing1, Chris Measures3, Clifton Buck1, Kathleen Gosnell4, Maxime Grand3, Mariko Hatta3, and William Hiscock3

1Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, Florida, USA

2School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK 3Department of Oceanography, University of Hawaii-Manoa, Oahu, Hawaii, USA

4Department of Marine Sciences, University of Connecticut, Groton, Connecticut, USA

Project Overview Automated Trace Metal ExtractionBuilding on the method developed by Milne et al. 20102, we have automated much of the time-consuming process of extracting and preconcentrating trace metals from seawater.

References1 C.I. Measures, W.M. Landing, M.T. Brown, C.S. Buck, Limnol. Oceanogr.-Meth., 6 (2008) 384.2 A. Milne, W.M. Landing, M. Bizimis, P.L. Morton, Anal. Chim. Acta, 665 (2010) 200.

February-April 2007

Samples collected using CLIVAR trace metal rosette1

Twelve 12-L GO-Flo bottles 80 stations, 12 depths per station 1000 dissolved trace metal samplesCollected into acid-washed 125 mL LDPE bottles Acidified to 0.024 M HCl (using 6 M quartz distilled HCl)

To explore the biogeochemistry of dissolved trace metals in the Indian Ocean, from the Bay of Bengal to the Antarctic margin

Region of Study

Sample collection

Preparing the CLIVAR trace metal rosette for deployment

Sample analysisDissolved Fe and Al measured shipboard by Grand, Hatta, and Measures (data not shown) Dissolved Cd, Co, Cu, Mn, Ni, and Pb measured at Florida State University

y = 89355x + 87731R² = 0.9995

y = 96802x + 16288R² = 0.9998

y = 91268x + 650R² = 0.9982

y = 110203x + 214024R² = 0.9994

y = 79737x + 31617R² = 0.9982

y = 89609x + 43790R² = 0.9996

50000

100000

150000

200000

250000

300000

350000

0.0 0.2 0.4 0.6 0.8 1.0

Cou

nts p

er se

cond

Mn (nmol/kg)

Mn Standard Addition slopes

Results, to dateContoured trace metal data are shown with overlays of related physical parameters.

OCE 0649639

Method highlights40x sample preconcentration (20 mL into 0.5 mL)Streamlined UV-oxidation (minimal sample transfer)Automated sample uptake and elutionOnline buffering to pH 5.8-6.2 (ammonium acetate, 0.4 M)Six hours to extract 24 samples

System componentsNobias Chelate PA-1 chelating resin (polycarbonate column)Cetac ASX-500 Autosampler (sample uptake)Cetac ASX-100 Autosampler (fraction collector)Dynamax Rainin RP-1 peristaltic pumpsVici 10-port injection (2 position) valve

All components coordinated with FloZF v5.0 (GlobalFIA)

Extraction sequencePrecondition system with UV trace metal-free seawaterSample uptake: 10 minute 2 mL/min flow rateRinse: 1 mL UHP water (18 Mohm-cm)Elution: 0.5 mL 1.0 M HNO3 (QD or Optima)Wash: 1 mL 1.0 M HNO3 (QD or Optima)Conditioning: 4 mL 0.08 M NH4-acetate

QuantificationThermo ELEMENT 2 HR-ICP-MSIsotope dilution: Cd, Cu, Ni and PbStandard additions: Co and Mn

Certified against SAFe S, D1 and D2

Similar slopes indicate consistent buffering throughout extraction