Inductively coupled plasma detectors mass spectrometry

More recently for ultratrace determination and speciation of antimony compounds the so-called hyphenated instrumental techniques have been applied which combine adequate separation devices with suitable element-specific detectors. They include high-performance liquid chromatography (HPLC) connected on-line with heated graphite furnace (HGF) AAS (HPLC-HGF-AAS), hydride-generation atomic fluorescence spectrometry (HPLC-HG-AFS) or inductively coupled plasma (ICP) mass spectrometry (MS) (HPLC-ICP-MS) capillary electrophoresis (CE) connected to inductively coupled plasma mass spectrometry (CE-ICP-MS) and gas chromatography (GC) coupled with the same detectors as with HPLC. Reliable speciation of antimony compounds is still hampered by such problems as extractability of the element, preservation of its species information, and availability of Sb standard compounds (Nash et al. 2000, Krachler etal. 2001). Variants of anodic stripping voltammetry for speciation of antimony have also been applied (Quentel and Eilella 2002). 

The main purpose of the detector in a field-flow fractionation (FFF) system is to quantitatively determine particle number, volume, or mass concentrations in the FFF size-sorted fractions. Consequently, a number, volume, or mass dependent size distribution of the sample can be derived from detection systems applied to FFF [e.g., (UV-Vis) fluorescence, refractive index, inductively coupled plasma ionization mass spectrometry (ICPMS)]. Further, on-line light scattering detectors can provide additional size and molecular weight distributions of the sample. 

AAS = atomic absorption spectrometry GC/FID = gas chromatography/f1ame ignition detector GC/FPD = gas chromatography/f1ame photometric detector ICP/AES = inductively coupled plasma atomic emission spectroscopy ICP/MS = inductively coupled plasma with mass spectrometric detection... 

AMS = accelerated mass spectroscopy FAAS = flame atomic absorption spectrometry GC/ED = gas chromatography/electron capture detector GFAAS graphite furnace atomic absorption spectrometry ICP-AES = inductively couples plasma-atomic absorption spectrometry NA = not applicable NAA = neutron activation analysis... 

Mass spectrometry has also been linked to inductively coupled plasma detectors, see also Sections 1.6 and 1.9. 

Over the years, in trace and major element analysis in general, three detectors which are especially suitable for element-specific detection have been developed inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectrometry (ICP-AES) and graphite furnace atomic absorption spectrometry (GFAAS). 

Atomic absorption spectrometry is commonly used to measure a wide range of elements as shown in Table 2. Such techniques as flame, graphite furnace, hydride generation, and cold vapor are employed. Measurements are made separately for each element of interest in turn to achieve a complete analysis these techniques are relatively slow to use. More sensitive, but also more expensive, multielement analytical techniques such as inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry can be used if lower (pgl and below) detection limits are required. These detectors can also be coupled with separation systems if speciation data, e.g., Cr(III) and Cr(VI), are needed. 

When gas chromatography is used to separate organometallic compounds, a number of detectors can be used. Conunon detectors such as Ihe FID, FPD, ECD, and MS have been employed. The most sensitive and selective detector for organometallic species is the atomic emission detector (113). The effluent from the GC enters a small chamber, and a microwave radiation is used to generate plasma. The intensity of the atomic emission radiation from the metal is monitored at a specific wavelength. Sometimes gas chromatography is interfaced with other instrumentation, such as atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICPAES), inductively coupled plasma mass spectrometry (ICPMS), to detect the metal species. 

Multiple-collector inductively coupled plasma mass spectrometry (MC-ICPMS) combines sector-field ICPMS with a multiple collector detector system and has recently emerged as an alternative to TIMS for precise U-Th isotope measurement. The full potential of MC-ICPMS has yet to be realized. Yet despite this, its performance in high precision isotope measurement already challenges and, in some cases, surpasses that ever achieved by TIMS (e.g., Lee and Halliday 1995 Blichert-Toft and Albarede 1997). 

Secondary Ion Mass Spectrometry Basic Concepts, Instrumental Aspects, Applications and Trends. By A. Benninghoven, F. G. Ruenauer, and H.W.Werner Analytical Applications of Lasers. Edited by Edward H. Piepmeier Applied Geochemical Analysis. By C. O. Ingamells and F. F. Pitard Detectors for Liquid Chromatography. Edited by Edward S.Yeung Inductively Coupled Plasma Emission Spectroscopy Part 1 Methodology, Instrumentation, and Performance Part II Applications and Fundamentals. Edited by J. M. Boumans... 

Five different detectors are common in HPLC (1) UV, (2) refractive index (RI), (3) conductivity, (4) inductively coupled plasma atomic emission, and (5) mass spectrometry. A UV detector passes a specific wavelength of UV light... 

Transient signals are typically obtained in atomic spectrometry when samples are introduced by flow injection techniques or when the spectrometer is used as an element-specific detector in hyphenated techniques. Inductively coupled plasma mass spectrometry has nowadays become the detection technique of choice for multielement-specific detection in speciation as it allows multielemental... 

A 9 mL aliquot from each TIMS sample solution was submitted to the University of Georgia, Laboratory for Environmental Analysis, for inductively coupled plasma-mass spectrometry analysis (ICP-MS). A Perkin-Elmer Elan 6000 ICP-MS with quadrapole chamber mass detector system was used to analyze the solution for Ag, As, Cu, Sb, Sn, Pb, and Zn. Insufficient sample remained for further analysis or replicate samples. However, all appropriate blanks, dilutions, and standards were run. 

Atomic spectrometric methods Here, the entire sample is atomized or ionized either by flame or inductively coupled plasma and transferred into the detector. The most common techniques in this class are flame atomic absorption spectrometry (FAAS) and inductively coupled plasma mass spectrometry (ICPMS). A general characteristic of these methods is the determination of the total concentration of the analyte without the direct possibility of distinguishing its specific forms in the sample. 

Taylor, H. E., Garbarino, J. R., Murphy, D. M., and Beckett, R. (1992). Inductively coupled-plasma-mass spectrometry as an element-specific detector for field-flow fractionation particle separation. Anal. Chem. 64, 2036-2041. 

Inductively coupled plasma-mass spectrometry (ICP-MS) is a powerful technique that uses an inductively coupled plasma as an ion source and a mass spectrometer as an ion analyzer. It can measure the presence of more than 75 elements in a single scan, and can achieve detection limits down to parts per trillion (ppt) levels for many elements—levels that are two or three orders of magnitude lower than those obtained by ICP-AES (Keeler 1991). It is more expensive than ICP-AES and requires more highly skilled technical operation. Aluminum levels in urine and saliva were detected down to 0.02 g/mL and in blood serum to 0.001 g/mL using ICP-MS (Ward 1989). Speciation studies have employed ICP-MS as a detector for aluminum in tissue fractions separated by size-exclusion chromatography (SEC) with detection limits of 0.04 g/g in femur, kidney and brain (Owen et al. 1994). 

Ultraviolet-visible (UV-Vis) spectrophotometric detectors are used to monitor chromatographic separations. However, this type of detection offers very little specificity. Element specific detectors are much more useful and important. Atomic absorption spectrometry (AAS), inductively coupled plasma-atomic emission spectroscopy (ICPAES) and inductively coupled plasma-mass spectrometry (ICP-MS) are often used in current studies. The highest sensitivity is achieved by graphite furnace-AAS and ICP-MS. The former is used off-line while the latter is coupled to the chromatographic column and is used on-line . 

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