Inductively coupled plasma sources linear dynamic range

The major disadvantage of arc/spark emission spectroscopy is the instability of the excitation source. This problem can be virtually eliminated by the use of a plasma torch. The most common commercially available method uses an inductively coupled plasma (ICP), which is also called RF plasma, to excite the sample (13-19). The resulting spectrometers (Fig. 4) can simultaneously measure up to 60 elements with high sensitivity and an extraordinarily wide linear dynamic range. 

The objectives of this study were to quantify the trace metals in PM2 5 of Eastern and Western Canada, to analyze their annual and seasonal trends and identify their source origin, by evaluating a database of trace metal concentrations obtained over a 2-year period (May 2004-December 2006) from the NAPS network. Over 1000 PM2 5 samples collected at seven selected sites were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) after microwave assisted acid digestion. This technique offers low detection limits, wide linear dynamic range, multielement capability, ability to measure isotope ratios and high sample throughput. Principal Components Analysis (PCA) was used to identify sources of trace metals at each sampling site. 

The first commercial plasma atomic fluorescence spectrometer was developed by Demers and Allemand. Hollow cathode lamps are used as radiation sources and an inductively coupled plasma torch as an atomizer. Detection limits are reported for more than 30 elements. The linear dynamic range is normally 10 to 10. ... 

Since the intensity of the source does not affect sensitivity, but does influence the noise, the high-intensity source increases the DLs of this system by a factor of 2-5 over conventional AAS. The linear dynamic range of the system is 5-6 orders of magnitude, much broader than conventional AAS and similar to inductively coupled plasma-optical emission (ICP-OES) (discussed in Chapter 7). 

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