Electrothermal vaporization (ETV) ICP mass spectrometry is a method that combines the ability of the graphite furnace to handle complex samples with the detection power of ICP-MS. It is somewhat surprising, however, that most works reporting on the application of this method have only described the ''simultaneous'' (from the same tube firing) determination of 1-3 elements. Different authors have attributed this fact to the limited capability of the quadrupole filter (the most commonly used mass spectrometer in ICP-MS instrumentation) to deal with the transient signals that electrothermal vaporization produces. Nevertheless, recent works suggest that the real multi-element capabilities of ETV quadrupole-based ICP-MS might have been largely underestimated. A systematic study of the number of mass-to-charge ratios that can be ''simultaneously'' monitored in ETV quadrupole-based ICP-MS without degrading the precision, the sensitivity and the limits of detection has been carried out. Three elements with different furnace behaviours (Cd, Co and Ti) were chosen for the study. The effect of the dwell time and the way of processing the analytical data were also evaluated. The results indicate that, when using ETV-ICP-MS with a quadrupole-based instrument, no detrimental effects on the precision, detection limits and sensitivity occur as long as a critical value of three or four points to define the signal profile is achieved. This requirement corresponds to the possibility of monitoring more than 20 elements for a standard peak width of 1.5-2 s. Several options for further improvements are also discussed, including the possibility of separating (with respect to time) the vaporization of elements with different furnace behaviours.
The coupling of a graphite furnace to an ICP mass spectrometer results in a method that combines the suitability of the graphite furnace for handling solid samples with the detection power of ICP mass spectrometry (ICP-MS). Surprisingly, the majority of previous work devoted to solid sampling electrothermal vaporization (ETV) ICP-MS has only dealt with the determination of a single element, thereby wasting the pronounced multi-element capabilities of the detection method. In this work, solid sampling ETV-ICP-MS was used for the simultaneous determination of Co, Mn, P and Ti in two PET (polyethyleneterephthalate) materials, showing the suitability of the approach used for this kind of analysis. For this determination, the problems caused by the different furnace chemistry of the elements had to be tackled. In order to enable the determination of P, a combination of Pd and ascorbic acid was used as a chemical modifier. Different calibration methods-external calibration using either an aqueous standard solution or a solid standard and single standard addition-were studied and the results obtained were compared with those obtained by (i) ICP atomic emission spectrometry after sample dissolution and (ii) X-ray fluorescence. External calibration using a solid external standard and single standard addition were proved to be equally successful, but the latter is more practicable as only an aqueous standard solution is required
It is known that the accurate determination of ppm levels of sulfur in solid samples is very complicated. One of the approaches that have been evaluated in order to improve the detection limits for this element is the use of electrothermal vaporization (ETV) as an alternative means of sample introduction in ICP mass spectrometry. In this way, it is possible to achieve a significant decrease of the oxygen-based interferences. In this work, the possibilities of electrothermal vaporization ICP-MS for sulfur determination are extended one step further, as the direct determination of the analyte in two Bisphenol samples (about 0.3 and 2 mug g(-1)) is carried out. Bisphenol A is a precursor in the production of polycarbonate and epoxy resins, in which sulfur is present as an impurity. S-34 was the isotope selected for the determination. Palladium (0.5 mug) was found to be the best chemical modifier and is capable of both preventing analyte losses (up to a pyrolysis temperature of 400 degreesC) and improving the sensitivity. Some evidence as to the way in which it may act is also presented. Nitric acid was added as well in order to favour an efficient matrix removal prior to the release of the analyte. The resulting solid sampling-electrothermal vaporization-ICP-MS method combines very interesting features for this particular element: a high sample throughput (20-25 min per sample), a low limit of detection (4 mug g(-1)) and a reduced risk of analyte losses and/or contamination. Moreover, it presents some advantages over the dedicated sulfur analyzers that are very popular in the industry: low sample consumption (a few milligrams), multielement possibilities and the ability to use aqueous standard solutions for calibration. On the other hand, the overall method cannot be considered as very economic, but, for many laboratories that already own an ICP-MS instrument, the acquisition of an ETV device would be relatively inexpensive
Next to laser ablation (LA) also electrothermal vaporization (ETV) from a graphite furnace as a means of sample introduction opens possibilities for direct analysis of solid samples using inductively coupled plasma mass spectrometry (ICPMS). In this paper, it is demonstrated that solid sampling ETV-ICPMS is very well suited for the determination of metal traces in polyethylene. A limited multielement capability is often cited as an important drawback of ETV-ICPMS. However, by studying the effect of monitoring an increasing number of mass-to-charge ratios on the signal profile (integrated signal intensity and repeatability) of selected analyte elements, the multielement capability of (solid sampling) ETV-ICPMS was systematically evaluated, and the results obtained suggest that, with a quadrupole-based ICPMS instrument, at least 11 elements can be determined "simultaneously" (from the same vaporization step), in essence without compromising the sensitivity or the precision of the results obtained. In this work, the "simultaneous" determination of Al, Ba, Cd, Cu, Mn, Pb, and Ti in a polyethylene candidate reference material has been accomplished, despite the large variation in analyte concentration (from 5 ng/g for Mn to 500 microg/g for Ti) and in furnace behavior (volatility) they exhibit. To avoid premature losses of Cd during thermal pretreatment of the samples, Pd was used as a chemical modifier. Two different calibration methods--external calibration using an aqueous standard solution and single standard addition--were studied and the results obtained were compared with those obtained using neutron activation analysis (NAA) and/or with the corresponding (candidate) certified values (if available). Single standard addition was shown to be preferable (average deviation between ICPMS result and reference value < 3%), although--except for Ba--acceptable results could also be obtained with external calibration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.