Inductively coupled plasma optical emission detection limits

Soil samples were wet sieved into (a) 2-4 mm, (b) 1-2 mm, (c) 0.5-1 mm, (d) 250-500 i m, (e) 125-250 am, (f) 63-125 j,m and (g) <63 j.m fractions. A ferruginous/magnetic fraction (m) was also prepared from the 2-4 mm fraction. Soil fractions were crushed, digested with HNO3/HCI/HF/HCIO4 and then analysed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) for Al, Ca, Cu, Fe, K, Mn, Na, P, S and Zn. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to determine Ag, As, Cd, Pb and Sb because of the lower detection limits by this method. The mineralogy of selected samples was determined by qualitative X-ray diffractometry. 

Highly sensitive instmmental techniques, such as x-ray fluorescence, atomic absorption spectrometry, and inductively coupled plasma optical emission spectrometry, have wide application for the analysis of silver in a multitude of materials. In order to minimize the effects of various matrices in which silver may exist, samples are treated with perchloric or nitric acid. Direct-aspiration atomic absorption (25) and inductively coupled plasma (26) have silver detection limits of 10 and 7 flg/L, respectively. The use of a graphic furnace in an atomic absorption spectrograph lowers the silver detection limit to 0.2 a.g/L. 

Introducing samples to the plasma via liquids reduces sensitivity because the concentration of the analyte is limited to the volume of solvent that the plasma can tolerate. An electro-thermal method seems an obvious choice to increase the detection limit as it will vaporise entirely most neat samples or using an increased concentration of sample in a suitable solvent. The sample is placed on a suitable open graphite rod in an enclosed compartment and heated rapidly (Figure 2.15). The electronics required for ICP-OES-ETV (inductively coupled plasma-optical emission spectroscopy-electro-thermal volatilisation) is similar to that for A AS and detection limits are better than ICP-AES. 

Each experiment was accortqjanied the determination of Pd in solution after hot filtration of the solid catalyst at the end of the reaction. Because simple Atomic Absorption Spectroscopy (AAS) was found to not be precise enough for the palladium analysis in this concentration range (detection limit too high.) ICP-OES and/or ICP-MS (Inductively Coupled Plasma - Optical Emission Spectroscopy or Inductively Coupled Plasma - Mass Spectrometry) were applied. To first approximation, the Pd leaching could not be correlated with the properties of the twelve different Pd/C catalysts described above ((1) Correlation of catalyst structure and activity.) There is, however, a strong correlation with the reaction parameters as described below. 

Tire three strong Tell lines were used as sensitive emission lines for the determination of Tc by inductively coupled plasma optical emission spectrometry (ICP-OES), which achieves a detection limit of around 4 pg Tc/1. The convenience of this approach makes it particularly suitable for on-line HPLC detection in speciation studies at enhanced environmental technetium levels [39]. Examples of this type of procedure for the determination of elements arc described in reviews [40,41 ]. 

Trace amounts of titanium can be determined by X-ray fluorescence spectrometry, neutron activation analysis (NAA), atomic absorption techniques (AAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES). In case of AAS, a high-temperature flame (nitrous oxide, acetylene) is essential, and the optimum wavelengths are 364.3 and 365.4 nm the sensitivity is low. With the graphite furnace, a lower detection limit of approximately 0.5 xg L can be achieved. ICP-OES is especially sensitive, and is the recommended instrumental... 

McLeod et al. (1984) described the simultaneous determination of Na, K, Ca, Mg, Li. Cu, Fe and Zn in blood serum by flow-injection analysis - inductively coupled plasma optical emission spectrometry (FIA-ICP-OES) using aqueous synthetic multi-element solutions for calibration. With an injected volume of 20 fiL the performane data for copper in an 1 + 1 diluted serum ranged for precision from 1.1% to 2.2% with a detection limit of 0.01 mg/L. 

During the last decades methods such as Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), Inductively Coupled Plasma Mass Spectroscopy (ICP-MS), and Resonance Ionization Mass spectrometry (RIMS) have decreased the need for selective radiochemical procedures. Many long-lived radionuclides today have lower detection limits if using, e.g., ICP-MS than if performing radiometric measurements with reasonable measuring times. At present, the half-life limit is a few hundred years, i.e., nuclides with longer half-hfe (e.g., Tc, Np, or Pu) should preferably be measured by ICP-MS and more short-... 

The analytical performance of ICP-MS is compared with other analytical techniques for the determination of trace metal oxide particulates after the simulated detonation of an RDD [10]. Table 20.9 shows a comparison of the instrumental parameters used in inductively coupled plasma optical emission spectroscopy (ICP-OES) and an ICP-MS instrument. These two techniques were used to analyze Sr, Ti, and Ce in ceramic oxides that may be used in RDDs. ICP-MS provided lower detection limits for the metals than ICP-OES. Overall method performance was comparable with ICP-OES and instrumental neutron activation analysis (INAA), another well-established nuclear and radiological analytical technique. 

Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES orICP-AES) This is one of the commonly deployed methods to determine the concentration of uranium in liquid samples, particularly when a multielement assay is required. A method involving solid phase extraction (SPE) on a mesoporous silica sorbent for 100-fold preconcentration of uranium and thorium from 100 mL aqueous samples prior to measurement with ICP-OES was described (Yousefi et al. 2009). Limit of detection was reported as 0.3 pg L. A slightly different approach, using octadecyl-bonded silica in the presence 2,3-dihydro-9,10-dihydroxy-l,4-anthracenedion, for preconcentration prior to ICP-OES analysis was also presented (Daneshvar et al. 2009). 

A novel technique of atomisation, known as vapour generation via generation of the metal hydride, has been evolved, which has increased the sensitivity and specificity enormously for these elements [5-7]. In these methods the hydride generator is linked to an AAS (flame graphite furnace) or inductively coupled plasma-optical emission spectrometer (ICP-OES) or an inductively coupled plasma mass spectrometer (IPC-MS). Typical detection limits achievable by these techniques range from 3 pg/1 (arsenic) to 0.09 pg/1 (selenium). 

Inorganic pigments and lakes (organic dyes bonded to an inorganic support) can be recognized by the ratio of elements in their composition, making elemental analysis an important tool in their identification. EDS may facilitate an initial qualitative analysis, but quantitative analysis and the detection of trace elements are needed to identify the inorganic colorant components. Due to sample size restrictions, the methods that can be employed are limited. The techniques of inductively-coupled plasma mass spectrometry (ICP-MS), ICP-optical emission spectroscopy (ICP-OES), and laser ablation ICP-MS are described in the literature (56). 

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