Isotope Ratio Measurements by Quadrupole based ICP-MS

Numerous applications of quadrupole ICP-MS (without a collision ceU) for isotope ratio measurements can be found in quite different fields. For example, magnesium isotope ratios on 

NIST SRM 980 and in spiked plant nutrient solutions for tracer experiments in biological research have been performed using the Elan 6000 (Perkin Elmer).The accuracy of the measured isotope standard solution-NIST SRM 980 and enrichments with spike - was 

The introduction of the collision cell in ICP-MS represents progress in ICP-MS instrumentation which is relevant for improving the precise determination of isotope ratios in comparison to commercial quadrupole ICP-MS without a collision cell. The first investigation of the basic principles and application of the collision cell to improve sensitivity in inorganic ultrasensitive mass spectrometry was published 24 years ago by Becker and Dietze.  

ICP-MS with a hexapole collision cell is advantageous for isotope ratio measurements of difficult to analyze elements. Due to possible interferences with Ar+, ArO+ and dimer argon molecular ions Ar2 the measurements of the isotope ratios °Ca/ Ca, Fe/ Fe and Se/ Se by ICP-MS are extremely difficult or completely impossible. Whereas for these isotope ratios precisions between 0.2 and 0.3 % were observed using ICP-MS with hexapole collision cell, a precision of 0.07% was measured for a lOp-gF uranium isotope reference solution 1) in the 

Moens et cd demonstrated that ion-molecule reactions in a dynamic reaction ceU (DRC) of ICP-QMS allow the Rb / Sr+ isobaric interference to be eliminated. A special ion-molecular reaction in a collision cell was studied in order to avoid this isobaric interference of atomic ions 

---