Inductively Coupled Plasma spectrometry

Inductively Coupled Plasma spectrometry (ICP) is a chemical analytical method allowing the determination of almost all the elements simultaneously thanks to the high temperature of the argon plasma (> 8000°C).

Solid samples should be dissolved, usually by acid digestion or by fusion. This step can also be carried out by microwave. The preparation of the sample before its passage in ICP is very important and it is necessary to take care not to contaminate and to avoid any loss in elements of interest. This must be introduced into the plasma in a finely vaporized form because the equipment does not allow particles larger than on micrometer to be treated during their passage through the plasma.

This technique consists, firstly, in spraying the liquid (or solid solution) sample into the nebulizer. Within the argon plasma, the ionized gas transmits part of its energy to the sample to atomize, excite, or even ionize it. The reaction, which takes place in a plasma torch, is initiated and maintained by an HF magnetic field induced by an induction coil. The introduction takes place in the center of the plasma, parallel to the flow of plasma gas.

The ions from the ionized sample are detected and quantified, either with an Atomic Emission Spectrometer (AES) or with a Mass Spectrometer (MS).