Double-focusing ICP-MS for the analysis of biological materials

The advantages and application of double-focusing (DF) inductively coupled plasma-mass spectrometry (ICP-MS) for the analysis of biological materials are described. The instrument combines a magnetic sector with an electrostatic sector and provides higher mass resolution by changing the widths and exist silts. The application of DF-ICP-MS to measure stable isotopes, which are used as tracers to study the absorption and matabolism of essential and toxic elements, is of great importance in biology and medicine. The ability for high-precision isotope ratio measurements afforded by DF-ICP-MS along with its extreme sensitivity at low resolution enables trace element speciation in biological materials.