Special new techniques of atomic spectrometric methods for trace analysis of high purity metals

How spectral interferences of analyte ions with polyatomic ions containing matrix atoms can be identified, reduced or eliminated was demonstrated for different pure metals using a double focussing ICP mass spectrometer in higher mass resolution. An in-situ coating procedure of the nickel inlet cones of the ICP mass spectrometer with a thin quartz glass film was developed in our laboratory. It leads to a drastic decrease of memory effects and blanks, especially for the analytes Na, Ni and Li. The limits of determination (LODs) of these analytes were decreased for more than one order of magnitude. The analytical performance of two atomic spectrometric techniques combined with electrothermal vaporization (ETV) of metallic microsamples was investigated using tungsten as an example. An ICP optical emission spectrometer equipped with ETV (ETV ICP OES) as well as a solid sampling atomic absorption spectrometer (SS-ET AAS) were used. Benefits and drawbacks of both method combinations were summarized and compared. The multielement capability of ETV ICP OES was much higher than the of SS-ET AAS. LODs of the less refractory analytes were lower with SS-ET AAS than with ETV ICP OES