Use of external calibration for the determination of trace metals in biological materials by inductively coupled plasma mass spectrometry

Abstract

Inductively coupled plasma mass spectrometry (ICP-MS) was used for the analysis of two marine biological materials (cod liver tissue and shellfish tissue). A rapid dissolution of the materials was achieved by digestion in pressurised vessels in a microwave oven. Twelve elements (Cr, Fe, Mn, Ni, Cu, Zn, As, Ag, Cd, Sn, Hg and Pb) were then determined. It was possible to obtain accurate results by external calibration (i.e., the use of standard solutions), even at sub-µg g^–1 levels. Internal standardisation using ⁴⁰Ar⁴⁰Ar was carried out when required to correct for instrumental drift. The isotope dilution technique generally gave more accurate and precise results, especially at the lower concentration levels.