Mass Bias in MC-ICP-MS

Mass bias in MC-ICP-MS varies with both time and nuclide mass. Since calibration is typically performed sequentially in a calibrator-measurand-cahbrator bracketing mode, the effect of time has to be separated from that of mass in the mass bias correction model. Hence the logic of creating a mass bias discrimination model is to express the calibration factor, Ki/j, as a product of two functions one that varies with time only and the other that varies with the nuclide masses only [16, 17, 19]. For example,... 

The ability to accurately correct for mass bias in MC-ICP-MS is critical to achieving high-accuracy isotope ratio analyses. The ideal way of doing this is to use a stable isotope pair internal to the element system of interest. This internal normalisation approach is applicable for multiisotope systems where one or more isotopes are partly radiogenic in origin (e.g. Lu Hf)... 

---