ICP-OES: inductively coupled plasma – optical spectrometry

The choice of an analytical method is determined above all by the species of interest, their number and the concentrations sought, but also by the sample matrix and the interferences it is likely to generate. In addition to investment and operating costs, the choice of analytical rate should also be taken into account. As far as elemental analysis is concerned, no atomic spectrometry technique can yet claim to combine all the desired qualities. Of all the techniques available today, ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry) or ICP-AES (-Atomic Emission Spectrometry), commercially introduced in 1974, is particularly widespread in Western laboratories and is becoming increasingly popular in emerging countries.

To avoid confusion with Auger spectrometry, IUPAC generally recommends the use of OES.

This relatively easy-to-use quantification technique is based on the optical spectrometric analysis of photons generated by an inductively coupled plasma. In addition to achieving detection limits of the order of μg/L in the dissolved phase and less than mg/kg in the solid phase, it is also the only technique that supports the introduction of highly saline liquid samples and the analysis of organic solvents with relative ease. What's more, it features a wide range of determinable elements (over 70) and a high analytical throughput. All these features amply justify its success.

In addition to a theoretical review, this article provides an in-depth description of the equipment, including recent developments. It highlights the problems associated with interference and ways of correcting them, and presents the technique's performance and numerous application examples.