Isotope dilution analysis of selenite and selenate in natural water using microwave-induced nitrogen plasma mass spectrometry.
Isotope dilution analysis of the sub-microg l(-1) levels of selenite and selenate in natural water samples by microwave-induced nitrogen plasma mass spectrometry (MIP-MS) was performed. An appropriate amount of a spike solution containing 78Se-selenite and 78Se-selenate was added to the natural water sample to be analyzed. Both analytes in the water were then concentrated simultaneously by passing the sample through a column that was filled with an anionic exchange resin. After the concentration process, all of the selenite and some of the selenate on the resin were eluted by 0.03 M nitric acid. The residual selenate was eluted by 0.13 M nitric acid. The eluted sample solutions were injected into MIP-MS, and isotope dilution analyses were carried out. Selenite and selenate concentrations as low as 0.01 microg l(-1) in the natural water sample were successfully determined by the proposed method.
Instrumental Analysis Center, Kitami Institute of Technology, 165 Koen-cho, Kitami 090-8507, Japan. minamihr@mail.kitami-it.ac.jp
Hirotsugu
H
Minami
Wanhong
W
Cai
Tatsuya
T
Kusumoto
Kaiji
K
Nishikawa
Qiangbin
Q
Zhang
Sadanobu
S
Inoue
Ikuo
I
Atsuya
D005618:Fresh Water / Q000032:analysis*; D007554:Isotopes; D013058:Mass Spectrometry / Q000379:methods*; D064586:Selenic Acid; D018036:Selenium Compounds / Q000032:analysis*; D018038:Sodium Selenite / Q000032:analysis
D007554:Isotopes; D018036:Selenium Compounds; D018038:Sodium Selenite; D064586:Selenic Acid