Determination of trace levels of iron in a seawater sample using isotope dilution/inductively coupled plasma mass spectrometry.
An analytical method for trace levels of iron in a seawater sample using isotope dilution ICP-MS was developed. Preconcentration of iron and the removal of major elements in seawater such as alkali and alkaline-earth elements can be carried out quickly using a chelating resin disk by adjusting the sample pH to 3. The collision cell option of the ICP-MS instrument method was used to improve the performance of the instrument for iron measurements since ArO and ArN interferences could be reduced using this analytical method. About 4 ml min(-1) helium, as the collision gas, were introduced into the cell. 40Ar14N and 40Ar16O which interfere with 54Fe and 56Fe in water had their amounts decreased by 5 orders of magnitude. Then, the isotope dilution method was used for iron determination below ng g(-1) level of trace iron in four environmental reference materials (river water standard sample JAC-0031 (Japan Soc. for Analytical Chemistry), estuarine standard sample SLEW-2 (NRC Canada) and seawater standard samples CASS-3 and NASS-5 (NRC Canada)) were measured. Good agreement between analytical results and certified values of reference materials was obtained, which confirmed the effectiveness of this method.
Institute for Environmental Sciences, Department of Radioecology, Ienomae, Obuchi, Rokkasho-mura, Kamikita-gun, Aomori, Japan.
Yuichi
Y
Takaku
Takuma
T
Hayashi
Ikuko
I
Ota
Hidenao
H
Hasegawa
Shinji
S
Ueda
D001128:Argon / Q000032:analysis; D002614:Chelating Agents / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006371:Helium / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D007201:Indicator Dilution Techniques; D007501:Iron / Q000032:analysis* / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D009584:Nitrogen / Q000032:analysis; D012623:Seawater / Q000032:analysis*; D013997:Time Factors; D014131:Trace Elements
D002614:Chelating Agents; D014131:Trace Elements; D006371:Helium; D001128:Argon; D007501:Iron; D009584:Nitrogen