Inductively Coupled Plasma Optical Emission Spectrometry

Abstract

Inductively coupled plasma optical emission spectrometry (ICP‐OES) is a powerful tool for simultaneously determining many elements in a variety of sample matrices. With this method, liquid samples are injected into a radio frequency (RF)‐induced argon plasma using one of a variety of nebulizers or sample introduction strategies. The sample aerosol reaching the plasma is quickly dried, vaporized, and energized through collisional excitation at high temperature (up to 10 000 K). The atomic emission emanating from the plasma is viewed in either a radial or axial configuration, collected with a lens or mirror, and imaged onto the entrance slit of a wavelength selection device. Simultaneous multielement determinations are performed for up to 70 elements with the combination of a polychromator and an array detector. The analytical performance of such a system is competitive with most other inorganic analysis methods, especially with regard to sample throughput and sensitivity.

Response of potato to fertilizers applied on different soil types in Kenyan Highlands

“…Soil pH (soil/water ratio, 1:2.5) was measured using a pH meter, total N by modified micro‐Kjeldahl method (Bremner, 1996), and organic carbon by modified Walkley–Black method (Nelson & Sommers, 1996). Extraction of soil samples for analysis of P, K, Ca, Mg, Fe, Mn, B, Zn, and Cu was done using Mehlich 1 procedures (Mylavarapu et al., 2002) and determined using inductively coupled plasma–optical emission spectrometry (Hou & Jones, 2000). Cation exchange capacity was analyzed following procedures provided by Polemio and Rhoades (1977).…”

Is MIP-OES a suitable alternative to ICP-OES for trace element analysis?

“…As more electrons are released in this process, and charged gas particles also gain kinetic energy, a chain reaction takes place and the plasma is formed. 7,8 Fig. 1 shows the schematic diagrams for plasma generation using either an Ar-ICP or a Hammer cavity N 2 -MIP.…”

“…Interestingly, MIPs may be run under normal or reduced pressure with Ar, He, N 2 , CO 2 , Ar/He, or N 2 /O 2 , with N 2 being the most common choice. 4,7–9 Initially, the gas continuously flows through the torch, and a high-voltage spark is used to seed electrons that will start the plasma generation process. 1,8 In Ar-ICP-OES, an alternating radiofrequency (RF) generator (usually at a frequency of 27 or 40 MHz) is applied to the induction coil, generating an oscillating magnetic field (MF) whose force lines follow closed elliptical paths.…”

“…1,8 In Ar-ICP-OES, an alternating radiofrequency (RF) generator (usually at a frequency of 27 or 40 MHz) is applied to the induction coil, generating an oscillating magnetic field (MF) whose force lines follow closed elliptical paths. 1,7,8 In N 2 -MIP-OES, microwave (MW) energy is applied into a tuned resonant cavity filled with N 2 , giving rise to an axial MF and a radial electric field (EF). The instrumental components used for MW generation (magnetron and power supplies) are relatively inexpensive, as they are the same 2.45 GHz frequency systems used in kitchen microwave ovens.…”

“…1A). 7,8 More recently, a flat-plate arrangement was introduced by PerkinElmer. Two aluminum flat plates, which are perpendicular to the sample flow, replace the induction coil and create a more uniform discharge.…”