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1.
Talanta ; 128: 379-85, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25059175

RESUMO

This work explores the multi-element capabilities of inductively coupled plasma-mass spectrometry with collision/reaction cell technology (CCT-ICP-MS) for the simultaneous determination of both spectrally interfered and non-interfered nuclides in wine samples using a single set of experimental conditions. The influence of the cell gas type (i.e. He, He+H2 and He+NH3), cell gas flow rate and sample pre-treatment (i.e. water dilution or acid digestion) on the background-equivalent concentration (BEC) of several nuclides covering the mass range from 7 to 238u has been studied. Results obtained in this work show that, operating the collision/reaction cell with a compromise cell gas flow rate (i.e. 4 mL min(-1)) improves BEC values for interfered nuclides without a significant effect on the BECs for non-interfered nuclides, with the exception of the light elements Li and Be. Among the different cell gas mixtures tested, the use of He or He+H2 is preferred over He+NH3 because NH3 generates new spectral interferences. No significant influence of the sample pre-treatment methodology (i.e. dilution or digestion) on the multi-element capabilities of CCT-ICP-MS in the context of simultaneous analysis of interfered and non-interfered nuclides was observed. Nonetheless, sample dilution should be kept at minimum to ensure that light nuclides could be quantified in wine. Finally, a direct 5-fold aqueous dilution is recommended for the simultaneous trace and ultra-trace determination of spectrally interfered and non-interfered elements in wine by means of CCT-ICP-MS. The use of the CCT is mandatory for interference-free ultra-trace determination of Ti and Cr. Only Be could not be determined when using the CCT due to a deteriorated limit of detection when compared to conventional ICP-MS.


Assuntos
Elementos Químicos , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Vinho/análise , Amônia , Cromo/análise , Gases , Hélio , Hidrogênio , Reprodutibilidade dos Testes , Titânio/análise
2.
Anal Chim Acta ; 691(1-2): 18-32, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21458627

RESUMO

The analysis of wine is of great importance since wine components strongly determine its stability, organoleptic or nutrition characteristics. In addition, wine analysis is also important to prevent fraud and to assess toxicological issues. Among the different analytical techniques described in the literature, atomic spectrometry has been traditionally employed for elemental wine analysis due to its simplicity and good analytical figures of merit. The scope of this review is to summarize the main advantages and drawbacks of various atomic spectrometry techniques for elemental wine analysis. Special attention is paid to interferences (i.e. matrix effects) affecting the analysis as well as the strategies available to mitigate them. Finally, latest studies about wine speciation are briefly discussed.


Assuntos
Espectrofotometria Atômica/métodos , Vinho/análise , Metais/química , Metais/normas , Compostos Orgânicos/química , Compostos Orgânicos/normas , Controle de Qualidade , Sais/química , Espectrofotometria Atômica/normas
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