CCQM-K12.1 International Comparison on the Determination of Serum

The determination of creatinine in human serum by liquid chromatography-isotope dilution mass spectrometry is described. The method is based on the addition of a known weight of labeled creatinine as internal standard according to the serum weight to be detected. Measurement of the intensity ratio of natural to labeled ions was conducted by selected ion monitoring (SIM).The results of the CCQM-K12.1 key comparison on the determination of serum creatinine are posted in details.