Noise characteristics and analytical precision of inductively coupled plasma mass spectrometry using a Vulkan direct injection nebuliser for sample introduction

文献情報

出版日 2005-12-20

DOI 10.1039/B514503A

インパクトファクター 4.023

著者

Daniel Goitom, Erik Björn

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要旨

Noise and precision of ion count rate measurements were characterised for ICP-MS using a Vulkan direct injection nebuliser (Vulkan DIN) for sample introduction. For comparison, experiments were also carried out using a direct injection high efficiency nebuliser (DIHEN). The Vulkan DIN gave considerably higher relative white noise compared with the DIHEN, −40.3 compared with −45.8 dB, and measurements of aerosol characteristics showed that this was a result of broader size distribution and larger mean size of droplets for the Vulkan DIN. At a liquid flow rate of 85 μL min−1, the aerosol volume fraction constituted by droplets with a diameter smaller than 10 μm was only 5% for the Vulkan DIN compared to 38% for the DIHEN, and the Sauter mean diameter was 30.2 and 11.1 μm, respectively. Compared with the DIHEN, interference noise from a peristaltic pump was very small with the Vulkan DIN because at the liquid flow rate giving maximum sensitivity, the analyte signal intensity was not much affected by changes in liquid flow rate. Although this had a positive effect on precision, it indicated that the plasma is cooled by large droplets that do not positively contribute to the analyte signal intensity. For analytical precision data it was evident that with the Vulkan DIN, precision was limited by the high white noise in the frequency range 0.4–500 Hz, but for the DIHEN there were relatively large contributions from 1/f and/or interference noise to the observed precision. When using integration times of 1000 ms or longer, the DIHEN did, however, appear to give slightly better precision for most of the isotopes tested. For comparison, precision data was also generated when using a conventional spray chamber sample introduction system and it was found that, with a 3000 ms integration time, both direct injection nebulisers gave better precision for most isotopes. Although analytical precision is impressive, the results in this paper also show that both direct injection nebulisers produce aerosols that are far from ideal for the types of ICPs currently used in commercial instruments.

掲載誌

Journal of Analytical Atomic Spectrometry

CiteScore: 6.2

自己引用率: 25.8%

年間論文数: 254

The Journal of Analytical Atomic Spectrometry (JAAS) is the central journal for publishing innovative research on fundamentals, instrumentation, and methods in the determination, speciation and isotopic analysis of (trace) elements within all fields of application. This includes, but is not restricted to, the most recent progress, developments and achievements in all forms of atomic and elemental detection, isotope ratio determination, molecular analysis, plasma-based analysis and X-ray techniques. The journal welcomes full papers, communications, technical notes, critical and tutorial review articles, editorials, and comments, in addition to the Atomic Spectrometry Updates (ASU) literature reviews that are prepared by an expert panel. Submissions are welcome in the following areas, but note this list reflects the current scope and authors are strongly encouraged to contact the Editorial team if they believe that their work offers potentially new and emerging research relevant to the journal remit: Fundamental studies in the following. New and existing sources for atomic emission, absorption, fluorescence and mass spectrometry and those that provide both atomic and molecular information Sample introduction techniques for solids, liquids, gases Improvements in sensitivity, selectivity, precision, accuracy and/or robustness Isotope ratio measurements, including techniques for improving precision and mass bias correction Single channel and multichannel simultaneous detection systems Chemometrics, statistics, calibration techniques and internal standardisation Theoretical and numerical modelling of fundamental processes related to all of the above methodologies Novel or improved methodologies in areas of application including, but not limited to the following. Biosciences, including elemental, speciation and isotopic analysis in biological systems, immunoassays based on metal-labeled antibodies, bio-imaging, and nanoparticle toxicology Geochemistry Environmental science Materials science, including engineered nanoparticles and quantum dots Metrology, including reference materials Forensic analysis Food and agricultural sciences Energy Archaeometry Molecular analysis. Molecular sources for elemental and isotopic analysis Atomic sources for molecular analysis Atomic and molecular techniques simultaneously used for complementary chemical information All contributions are judged on originality and quality of scientific content, and appropriateness of length to content of new science.