Abstract A GC-MS determination of urea in serum or spent dialysate is described, using 13 C
15 N 2-labelled urea and assaying the area ratio of labelled to natural urea by mass …

A selected ion-monitoring method, incorporating an internal standard, was developed to
allow the direct and simultaneous measurement of stable isotopelabelled urea and …

An Isotope dilution mass spectrometrlc (ID/MS) method for serum urea Is described. The
method utilizes urea-180 as the labeled Internal standard and Involves Isolation of urea from …

The study of urea metabolism In humans necessitates sen-sitive methods, so that very low
Isotopic enrichments of plasma or urinary urea can be measured. A stable derivative of urea …

Measurements of serum urea concentration in monitoring of renal functions or of protein
metabolism have been performed routinely in clinical laboratories. Recent recognition of the …

Background: A reference measurement procedure is needed to demonstrate the traceability
of results of urea measurements in human serum. We developed a measurement procedure …

A rapid and reproducible method is described for measurement of urea in biological
materials (after deproteinisation) and in serum (without deproteinisation). Urea is …

Using" high performance" liquid chromatography, we studied non-protein-bound fractions
and total concentrations of 18 solutes accumulating in sera from a group of 12 patients who …

A simple and rapid quantitative method for 13C-labelled urea ([13C] urea) in human serum
was developed by using high-performance liquid chromatography-atmospheric pressure …

A method for the measurement of uric acid in human serum by isotope dilution-mass
spectrometry is described. The analytical procedure consists of the following Steps:(1) …