Inductively Coupled Plasma-Atomic Emission Spectrometry: Analysis of Biological Materials and Soils for Major, Trace, and Ultra-Trace Elements

TLDR

An inductively coupled plasma with a coaxial nebulizer and poly‑chromator, coupled to wet‑digestion, dry‑ashing, and a single calibration curve, enables direct multielement determinations. The ICP method shows negligible matrix and interelement effects and delivers accuracy, precision, and sensitivity comparable to or better than neutron activation analysis, X‑ray fluorescence, solution‑rotating disk atomic emission, and flame atomic absorption spectrometry.

Abstract

An inductively coupled plasma sustained in flowing argon and a permanently aligned all-glass coaxial pneumatic nebulizer are employed in the atomic emission mode with a direct-reading poly-chromator for simultaneous multielement determinations. The inductively coupled plasma is shown to be remarkably free from matrix and interelement effects by application for the determination of major (Na, K, P, Ca, and Mg) and trace (Fe, Cu, Zn, Mn, Pb, Cd, Co, Cr, Ni, V, Ti, Al, Sr, and Ba) elements in reference biologic materials and soil extracts. Wet-digestion and several dry-ashing sample preparation procedures are evaluated. Accuracy, precision, and sensitivity compare favorably with other multielement instrumental techniques (neutron activation analysis, energy dispersive x-ray fluorescence, solution-rotating disk atomic emission spectrometry) and with flame atomic absorption spectrometry. The directness of the method reported here is illustrated by use of one set of system operating conditions with one set of synthetic reference solutions used to establish a single calibration curve for each element.