An Application of Nitrogen Microwave-Induced Plasma Mass Spectrometry to Isotope Dilution Analysis of Selenium in Marine Organisms.

Abstract

Nitrogen microwave-induced plasma mass spectrometry was studied for its applicability to the isotope dilution analysis of selenium in biological samples. Spectroscopic interference by calcium, which is present in high concentrations in biological samples, was investigated. No detectable background spectrum was observed for the major selenium isotopes of 78Se and 80Se. No detectable interferences by sodium, potassium, calcium and phosphorus on the isotope ratio 80Se/78Se were observed up to concentration of 200 mg/ml. The method was applied to the analysis of selenium in biological reference materials of marine organisms. The results showed good agreement between the certified and found values.

Application of a nitrogen microwave-induced plasma mass spectrometer as an element-specific detector for arsenic speciation analysis

“…15,17,21,22 In previous papers, we reported the use of high power N 2 -MIP-MS for the isotope dilution analysis of selenium in clinical and marine samples. 21,22 The methods are highly sensitive with a low detection limit, and are comparable to those of ICP-MS. 23 Very few papers concerning the coupling of HPLC with N 2 -MIP-MS for elemental speciation analysis, especially for arsenic, have been published.…”

Determination of Arsenic Compounds by High-Performance Liquid Chromatography-Ultrasonic Nebulizer-High Power Nitrogen-Microwave-Induced Plasma Mass Spectrometry: An Accepted Coupling

“…Urine contains a high amount of salt and the organic materials matrix. This causes serious analytical problems when it is directly injected into a HPLC system. , Lack of species separation and peak broadening owing to column overload appears also when the sample is injected directly to the column . With the direct injection of the 10−15 μL of urine, the separation of arsenic compounds in LC-SCX column is adequate 20 (Figure ).…”

“…A high power nitrogen MIP-MS having a rectangular waveguide and an Okamoto cavity (2.45 GHz, maximum 1.5 kW; constructed by Hitachi Co. Ibaraki, Japan) is one of these sources that is sustained by the nitrogen gas. − The plasma is doughnut shaped just the same as the Ar-ICP. It enables the introduction of sample aerosols directly into the center of the plasma. ,,− Because the interference of Ar-associated polyatomic ions is replaced with that of nitrogen-related polyatomic ions, MIP-MS could determine the arsenic without spectral interference. ,,− Surprisingly, only some scattered information with high power N 2 -MIP-MS has been reported for total elemental analysis. ,,, In earlier publications, our group and others reported use of the high power N 2 -MIP-MS for isotope dilution analysis of selenium in clinical and marine samples. , The methods are highly sensitive with low detection limit, which are comparable with that of ICPMS . Papers concerning the coupling of HPLC with N 2 -MIP-MS for elemental speciation analysis, especially for arsenic, are not well reported.…”

Isotope Dilution Analysis of Selenite and Selenate in Natural Water Using Microwave-Induced Nitrogen Plasma Mass Spectrometry

“…The most important characteristic of nitrogen MIP-MS for selenium analysis is that the nitrogen plasma does not produce any spectroscopic interfering molecular ions containing an argon atom, such as 38 Yoshinaga et al 28 and Shirasaki et al 29 reported the determination of selenium in biological samples by ID-MIP-MS. Ohata et al reported the determination of the total concentration of selenium in human blood serum by ID-MIP-MS with a hydride generation technique. 30 However, no study has been reported for the determination of sub-µg l -1 levels of selenite and selenate in natural water samples by ID-MIP-MS.…”