Calibration of isotope ratio analyses using international reference standards

As the isotope ratio is independent on the concentration of the compound of interest, calibration of the IRMS is not conducted over a certain concentration range, but over a range of delta values. The calibration should include at least two internationally accepted isotope standards. Moreover, working standards can be used, which are calibrated regularly against the international isotope standards.

This Technical Note shows the principle of calibration of an EA-IRMS instrumentation using international isotope standards, which is fully automatically done by the lyticOS^® Software Suite during the measurement sequence.