Polyatomic interferences, in ICP

There are troublesome spectral interferences, spectral line overlapping in ICP-OES, and polyatomic interferences in ICP-MS. 

Gluodenis, T.J., Jr. Sakata, K. i., and McCurdy, E. (1999). Minimizing polyatomic interferences in ICP-MS—The authors review the three commonly used methods for minimizing interferences in ICP-MS and discuss their use of a cool-plasma-based system involving a collision/reaction cell. Spectroscopy 14(3), 16. 

Several authors [386,387] have discussed the spectroscopic and nonspectroscopic (matrix) interferences in ICP-MS. ICP-MS is more susceptible to nonspectroscopic matrix interferences than ICP-AES [388-390]. Matrix interferences are perceptible by suppression and (sometimes) enhancement of the analyte signal. This enhanced susceptibility has to be related to the use of the mass spectrometer as a detection system. In fact, since both techniques use the same (or comparable) sample introduction systems (nebulisers, spray chambers, etc.) and argon plasmas (torches, generators, etc.), it is reasonable to assume that, as far as these parts are concerned, interferences are comparable. The most severe limitation of ICP-MS consists of polyatomic... 

To overcome polyatomic interferences in Q-ICP-MS a host of physical approaches (i.e., optimization of plasma parameters, addition of supplementary plasma gases, the use of alternative plasma gases or collision/dynamic reaction... 

Table 13.1 Spectral (isobaric and polyatomic) interferences in the detection of Rh, Pd, and Pt by ICP-MS...

Possible problems of interferences in ICP-MS were highlighted as well as the need to carry out a preconcentration step. Spectral interferences may occur for copper, leading to high results caused by spectral overlap from unidentified polyatomic species at mass 65. The existence of this species in natural samples was stressed in the certification of an estuarine water reference material by a mass spectrum obtained by high resolution ICPMS, although its exact composition could not be determined. 

Krushevska, A., Waheed, S., Nobrega, J., Amarisiriwardena, D., and Barnes, R. M. (1998). Reducing polyatomic interferences in the ICP-MS determination of chromium and vanadium in biofluids and tissues. Appl. Spectrosc. 52(2), 205. 

The almost continuous confrontation with polyatomic spectral interferences poses a serious problem in ICP-QMS analysis, because detection limits are degraded and the measured intensity is incorrectly attributed to the analyte ion. The problem of spectral interferences... 

Date AR, Ying Y, Stuart ME (1987) The influence of polyatomic ion interferences in analysis by inductively coupled plasma source mass spectrometry (ICP-MS). Spectrochim Acta 42B 3-20... 

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