Directly coupled plasma-optical emission

Neutron activation and petrographic analysis of late medieval Spanish pottery from the major Spanish production centers of Seville, Granada, Patema-Manises, Barcelona, and Talavera-Puente allowed progress to be made in uniquely characterizing these production centers (5-7). Efforts to identify different Mexican majolica productions petrographically have been unsuccessful, and an attempt at chemical characterization by directly coupled plasma-optical emission spectroscopy was later determined to have been flawed by problems encountered with the dissolution of the ceramic samples... 

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

In Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), a gaseous, solid (as fine particles), or liquid (as an aerosol) sample is directed into the center of a gaseous plasma. The sample is vaporized, atomized, and partially ionized in the plasma. Atoms and ions are excited and emit light at characteristic wavelengths in the ultraviolet or visible region of the spectrum. The emission line intensities are proportional to the concentration of each element in the sample. A grating spectrometer is used for either simultaneous or sequential multielement analysis. The concentration of each element is determined from measured intensities via calibration with standards. 

Thiel G, Danzer K (1997) Direct analysis of mineral components in wine by inductively coupled plasma optical emission spectrometry (ICP-OES). Fresenius J Anal Chem 357 553... 

N. Carrion, M. Murillo, E. Montiel and D. Diaz, Development of a direct hydride generation nebuliser for the determination of selenium by inductively coupled plasma optical emission spectrometry. Spectrochim. Acta, Part B, 58(8), 2003, 1375-1389. 

K. M. Hua, M. Kay, H. E. Indyk, Nutritional element analysis in infant formulas by direct dispersion and inductively coupled plasma-optical emission spectrometry, Food Chem., 68 (2000), 463-470. 

Van Borm W. A. and Broekaert J. A. C. (1990) Noise characteristics in inductively coupled plasma optical emission spectrometry using slurry nebulization and direct powder introduction techniques, Anal Chem 62 2527-2532. 

Emission spectroscopic techniques such as inductively coupled plasma optical emission (ICP-OES) and direct current plasma optical emission (DCP-OES). include the analysis of copper in biological materials (Delves et al.. 1983. Roberts et al., 1985). These techniques, with suitable sample preparation, have sufficient low bias and precision for clinical work but are more expensive and more complex than AAS (Herber et al.. 1982). Flow injection-ICP-OES will be mentioned below. 

In this vein, many appHcations have appeared in the literature on speciation of oxidation states, such as Cr(m)/Cr(VI), Fe(n)/Fe(m), As(III)/As(V), Se(IV)/ Se(VI). Also, FIA techniques have been used to preconcentrate Sn, Hg, and Pb organometallics mainly from natural waters, sediment, and soil extracts. In particular great interest has been focused into the speciation of chromium oxidation states in water samples at very low level (nanograms per liter). A FI system with a minicolumn of acidic preconcentration and inductively coupled plasma optical emission spectrometry (ICP-OES) for final detection was developed for a rapid speciation of Cr(VI) and Cr(III) in waters. On sample injection, Cr(VI) is retained in the alumina column whilst Cr(III) is not passing directly to the atomic detector. Afterwards, the retained Cr(VI) is eluted by injection of ammonium hydroxide, as shown in Figure 5, and its analytical signal of emission in the ICP-OES is registered. 

R. Erthal Santelli, E. Padua Oliveira, M. de F. Batista de Carvalho, M. Almeida Bezerra and A. Soares Freire, Total sulfur determination in gasoline, kerosene and diesel fuel using inductively coupled plasma optical emission spectrometry after direct sample introduction as detergent emulsions, Spectrochim. Acta B, 2008, 63(7), 800-804. 

GFAAS), inductively coupled plasma-atomic emission spectroscopy (ICP-AES - also referred to as inductively coupled plasma-optical emission spectroscopy, or ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS) are all routinely utilized in pharmaceutical applications. While there are other techniques of note available, such as micro-wave induced plasma (MIP) or direct coupled plasma (DCP), they have not been routinely used in the pharmaceutical industry, and will, therefore, not be discussed here. The theories involved in the use of FAAS, GFAAS, ICP and ICP-MS may be found in other articles of this Encyclopedia. 

Rabb, S. A. (2000). The investigation of concomitant species and acid matrix effects in inductively coupled plasma optical emission spectroscopy and mass spectrometry and preliminary studies of direct solids analysis. Unpublished Ph.D.Thesis, Ohio State University, Columbus. 

Broekaert J. A. C. and Leis F. (1985) An application of electrothermal evaporation using direct solids sampling coupled with microwave induced plasma optical emission spectroscopy to elemental determinations in biological matrices, Mikrochim Acta II 261-272. 

There are different spectrophotometric techniques for analysis of contaminants in biofuels. Simultaneous detection of the absorption spectrum and refractive index ratio with a spectrophotometer for monitoring contaminants in bioethanol has been carried out by Kontturi et al., 2011. Inductively Coupled Plasma Atomic Emission Spectrometry and optical emission spectral analysis with inductively coupled plasma (ICP-OES) have also been used to analyze biodiesel samples for trace metals (ASTM, 2007 ECS, 2006). An ICP-MS instrument fitted with an octopole reaction system (ORS) was used to directly measure the inorganic contents of several biofuel materials. Following sample prepwation by simple... 

Optical emision spectra nowadays are simply measured using a fiber optic cable that directs the plasma light to a monochromator, which is coupled to a photodetector. By rotating the prism in the monochromator a wavelength scan of the emitted light can be obtained. Alternatively, an optical multichannel analyzer can be used to record (parts of) an emission spectrum simultaneously, allowing for much faster acquisition. A spectrometer resolution of about 0.1 nm is needed to identify species. 

---