Inductively Coupled Plasma Optical Emission Spectrometry

Inductively coupled plasma optical emission spectrometry is a technique for qualitatively measuring major, minor and bulk trace elements in liquid suspensions and solids with digestion. Similar to HR-ICP-MS, the liquid sample is sprayed into an argon plasma where the dissolved metals are excited to emit their characteristic ultraviolet and visible radiation. The radiation is dispersed by a grating monochrometer and detected with a photomultiplier tube. Radiation wavelength is used to identify the element and intensity to determine analyte concentration. ICP-OES measures elements in the concentration range of 1 ppb (part-per-billion) to 1000 ppm (parts-per-million) or more. It is a particularly useful technique for measuring samples with dissolved solids (e.g., slurries and etchants) and samples containing both high and low concentration elements in the same solution (e.g., waste streams, raw water, RO concentrates, etc.).