Multivariate optimization of photochemical vapor generation for direct determination of arsenic in seawater by inductively coupled plasma mass spectrometry

Abstract

/npsi/ctrl?action=rtdoc&an=21277071&lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?action=rtdoc&an=21277071&lang=fr READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE.http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n'arrivez pas à les repérer, communiquez avec nous à PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. Questions? Contact the NRC Publications Archive team atPublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. If you wish to email the authors directly, please see the first page of the publication for their contact information. NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://doi.org/10.1016/j.aca.2015.10.020Analytica Chimica Acta, 2015-10 Multivariate optimization of photochemical vapor generation for direct determination of arsenic in seawater by inductively coupled plasma mass spectrometry Photochemical vapor generation (PVG) sample introduction coupled to inductively coupled plasma mass spectrometry (ICPMS) is described for the determination of As in seawater. A PlacketteBurman design (PBD) and central composite design (CCD) were employed to evaluate the significance of experimental variables relevant to the optimization of PVG-ICPMS detection. The impact of the saline matrix on the suppression of analyte signal was eliminated by use of a mixture of 20% (v/v) formic and 20% acetic acid (v/v) as the photochemical reductants. Optimized conditions yielded equivalent PVG generation efficiencies for As(III), As(V), monomethylarsonic acids (MMAs) and dimethylarsinic acids (DMAs), permitting direct and rapid determination of total arsenic in seawater without any other sample pretreatment. Quantitation was accomplished using one point gravimetric standard addition along with a spike of 82 Se internal standard to compensate for signal drift and fluctuation during analysis. The resulting method detection limit of 3 pg g À1 (3s) provided a 15-fold improvement over that obtained using direct solution nebulization, and is comparable to that for conventional chemical hydride generation (HG)-ICPMS. Accuracy was demonstrated by analysis of two Certified Reference Materials (NASS-6 and CASS-5 seawater) with satisfying results characterized by precisions of 3.5% and 3.2% RSD for CASS-5 and NASS-6, respectively. Crown

Photochemical Vapor Generation of Tellurium: Synergistic Effect from Ferric Ion and Nano-TiO2

“…PVG efficiency of arsenic was reported to be efficiently enhanced by using a mixture of LMWOAs. , The effect formic acid and acetic acid mixture on the Te PVG efficiency was studied. As shown in Figure b, by choosing acetic acid at 20% (v/v), approximate 40% improvement was obtained when formic acid was added between 2–5% (v/v).…”

“…Thus, the potential risks of humans exposing to tellurium are increasing. Due to unique feature of Te to form volatile species, photochemical vapor generation (PVG) is emerging as a promising analytical tool for its determination. − PVG utilizes free radicals as reductants, which is generated by photodecomposition of low molecular weight organic compounds (LMWOCs). , PVG can efficiently separate analyte from troublesome sample matrix and provide a very simple and green procedure for chemical vapor generation. − However, the low PVG generation efficiency of Te often limits its wide application in environmental samples with trace Te levels. , …”

“…5−7 PVG utilizes free radicals as reductants, which is generated by photodecomposition of low molecular weight organic compounds (LMWOCs). 5,8 PVG can efficiently separate analyte from troublesome sample matrix and provide a very simple and green procedure for chemical vapor generation. 9−17 However, the low PVG generation efficiency of Te often limits its wide application in environmental samples with trace Te levels.…”

Traditional Calibration Methods in Atomic Spectrometry and New Calibration Strategies for Inductively Coupled Plasma Mass Spectrometry

“…However, because there is no requirement for similar physicochemical properties nor close m/z values for analyte and IS, the element selected as an IS must present a high signal intensity, stable concentration, and have no signal overlap with the analyte. This strategy was also used by Gao et al ( 2015a , b ) to determine As and Sb in seawater and natural water by ICP-MS. As one would expect, the one-point standard addition calibration method is simpler, less expensive and faster than the traditional multi-level standard additions (Andrade et al, 2013 ). However, similar to EC, the more calibration points used, the more precise and accurate the results (Miller and Miller, 1984 ).…”

Estratégias de derivatização fotoquímica de compostos neutros para eletroforese capilar usando sistema UV/H>sub<2>/sub<O>sub<2>/sub< e construção de reator fotoquímico miniaturizado com TiO>sub<2>/sub<

“…ácido fórmico, acético e propiônico), os autores conseguiram demonstrar, ainda que com eficiência inferior ao método convencional (eficiência ~ 50 % ± 10), a formação de diferentes tipos de hidreto, de acordo com o ácido correspondente. Essa abordagem também tem sido aplicada para estudos de especiação e/ou determinação para outras espécies tais como arsênio (53,54) e mercúrio, (54) além de aplicações envolvendo o uso de TiO2. (54) Outras aplicações da utilização de POAs-UV para a análise elementar por técnicas espectroscópicas de absorção e/ou emissão em diferentes tipos de matrizes, abrangendo a remoção de matéria orgânica, degradação de compostos organometálicos prévia a derivatização química por HG.…”