Serum from patients was pooled, filtered, dispensed, and frozen. This pooled specimen was
used for accuracy control in 64 participating laboratories in Sweden. Mean values (" state-of …

We review recently developed reference methods based on mass fragmentography (specific
ion monitoring) with use of isotope-labeled internal standard, for determination of …

We report on the cooperation of two European Reference Laboratories for the determination
of reference method values in serum based materials intended for use in internal accuracy …

An Isotope dilution mass spectrometrlc (ID/MS) method for serum creatinine Is described
which uses creatlnlne-13C2 as the labeled Internal standard. Creatinine Is separated from …

This improved isotope-dilution gas chromatographic/mass spectrometric (GC/MS) method, in
which [13C] glucose is the internal standard, meets the requirements of a Definitive Method …

Determination of Creatinine in Human Serum by Isotope Dilution-Mass Spectrometry Page 1 L.
Siekmann: Determination of creatinine by isotope dilution-mass spectrometry \37 J. Clin. Chem …

Lyophilized samples of two serum pools, prepared commercially, were sent to 200
Canadian clinical chemistry laboratories for estimations of total cholesterol, sodium …

Isotope dilution and mass spectrometry were used in two independent laboratories to
determine cortisol in 15 plasma and serum pools used in the British and German national …

Using isotope dilution-mass spectrometry as reference method, we show that the kinetic
Jaffé method for determination of serum creatinine sometimes produces results that are …

Reference values for creatinine in serum were established using a fully enzymatic method,
adapted to a discontinuous analyzer. Our reference group included 250 females and 215 …