Simultaneous emission spectrometer

The current generation of inductively coupled plasma emission spectrometers provide limits of detection in the range of 0.1-500pg L 1 in solution, a substantial degree of freedom from interferences and a capability for simultaneous multi-element determination facilitated by a directly proportional response between the signal and the concentration of the analyte over a range of about five orders of magnitude. 

FIGURE 2.1 A diagram of a multi-photon microscope. For AF, SFIG and exogenous probe fluorescence only one laser is used. The fluorescence or SHG signal passes through a dichroic mirror to the detector(s). One or two detectors and the appropriate filters can be used to collect multiple emission signals simultaneously. A spectrometer can be placed in the detector path to collect spectra, or a polarizer can be used to collect polarization data. 

An inductively coupled plasma emission spectrometer does not require any lamps and can measure as many as —70 elements simultaneously. Color Plates 23 and 24 illustrate two designs for multielement analysis. In Plate 23, atomic emission enters the polychromator and... 

Color Plate 23 Polychromator for Inductively Coupled Plasma Atomic Emission Spectrometer with One Detector for Each Element (Section 21-4) Light emitted by a sample in the plasma enters the polychromator at the right and is dispersed into its component wavelengths by grating at the bottom of the diagram. Each different emission wavelength (shown schematically by colored lines) is diffracted at a different angle and directed to a different photomultiplier detector on the focal curve. Each detector sees only one preselected element, and all elements are measured simultaneously. [Courtesy TJA Solutions, Franklin, MA.J... 

Induced Coupled Plasma Spectrometry (ICP). An even more sensitive instrument has been developed to detect and quantitate, simultaneously, all inorganic species contained with a sample matrix. One such system is the ICP-OES (optical emission spectrometer) (Figure 25.5). The ICP-OES takes an aliquot of sample that has been acid digested and mixes it with a gas (e.g., argon) forming a plasma (i.e., an ionized gas) that is channeled into a nebulizer. Energy is applied to excite the atoms that are converted by the optics of the instrument into individual wavelengths. The... 

Judging from the degree of apparent interest and the number of papers published in the field of elemental TOF-MS over the last 3-4 years, it appears that this marriage is one full of promise for the future of elemental analysis. Perhaps the primary reason for such a trend is the need for a truly simultaneous mass spectrometer capable of extending capabilities beyond current instrumentation. The fields of ICP and GD atomic emission spectroscopy have been revolutionized by the incorporation of simultaneous array detectors. This revolution is just now beginning in the mass spectrometry field. 

The compositions of the products were determined by inductively coupled plasma (ICP) with a Perkin-Elmer plasma 40 emission spectrometer. Simultaneous differential thermal analysis and thermogravimetric (DTA-TG) curves were carried out by using Perkin-Elmer DTA-7000, TGA-7 PC series thermal analysis instrument in air with a heating rate of 10 °C /min. The infrared (IR) spectra were recorded on an Impact 410 IR spectrometer on samples pelletized with KBr powder. Valence states were determined by X-ray photoelectron spectroscopy (XPS). The XPS for powder samples fixed on double sided tapes was measured on an ESCA-LAB MKII X-ray photoelectron spectrometer. The Cis signal was used to correct the charge effects. 

An ICAP emission spectrometer in a commercial analytical laboratory can successfully provide accurate, precise multielement data (at major, minor and trace levels) for biological and human-related samples for many of the elements of interest for the related disciplines. The relative freedom from interferences is a very positive attribute. The analytical cost of operation is attractive whenever more than four elements must be analyzed in a sample. The inability of the experimental approach used here to provide analytical data for individual species of the elements is a definite disadvantage when this information is required. The primary requirement for ICAP-simultaneous multielement analysis is exceptionally careful analytical sample preparation methods and laboratory techniques. 

Fig. 99. Volatilization of dry solution aliquots from a graphite boat evaporation system coupled to a simultaneous ICP optical emission spectrometer at different heating currents [34],...

Figure 14.1 Atomic emission spectrometer. Basic concept and an example of a bench model of spectrometer, the Vista-Pro, CCD simultaneous ICP-OES (courtesy of Varian Inc, USA)...

Dedicated Analyzers. A wide choice of such systems, with varying degrees of automation, are available for clinical applications. One of the most prevalent is an atomic-emission spectrometer that generates both Na and K concentrations simultaneously on separate readouts a matter of seconds after a sample is aspirated. Automatic dilutors are commonly built in. Auto samplers and printers are generally available as optional attachments. Some of these systems are readily converted to Li assays when needed. 

Figure 7.27 A combination sequential-simultaneous ICP emission spectrometer. Such a combination permits rapid multielement analysis using the polychromator and preselected wavelengths. The monochromator adds the flexibility to monitor additional elements or alternate wavelengths in case of spectral interferences. [Courtesy of Jobin Yvon, Inc., Horiba Group, Edison, NJ (www. jyhoriba.com).]...

A Charge-lnjectioii Device Instrumeat. A number of companies offer multichannel simultaneous spectrometers based on echelle spectrometers and two-dimensional array devices. This type of instrument has replaced other types of multichannel emission spectrometers in many applications. 

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