… The reasons for conversion of urea into barbiturate prior to mass fragmentography in the
present work were the following: (1) Urea in itself is very difficult to analyze by gas …

… reference methods based on mass fragmentography (specific ion monitoring) with use of
isotope-labeled internal standard, for determination of cholesterol, triglycerides, urea, glucose, …

… of uric acid obtained with the massfragmentographic … serum pool was prepared and the
concentrations of cholesterol, creatinine, uric acid, urea, glucose, and cortisol were determined …

… In the present investigation, a reference measurement procedure for the determination of
urea in serum based on the principle of ID-MS is described. The combination of GC/MS and ID …

… from 100 to 300 amu Mass fragmentography of urea was performed in the EI mode by
monitoring mass fra~ents de = 153 (natural urea) and m/e = 156 (labelled urea) and calculation (…

… Isotope dilution mass fragmentography is an analytical technique with a relatively … serum
pool was prepared and the concentration determined of cholesterol, creatinine, uric acid, urea …

… A mass fragmentographic method for the determination of m-hydroxybenzoic acid, p-…
Statistical analysis between normal and uremic group could not be done, because the levels of the …

… mass spectrometric detection for the determination of pipecolic acid in urine and plasma (or
serum)… compound was tentatively identified as some heptafluorobutyrated derivative of urea. …

… A newer method involves the analysis of creatinine-containing fluids via gas chromatography
and mass spectrometry, called the mass fragmentographic process. All of the methods …

… mass fragmentography was used only to validate the simpler, more generally applicable
procedure of EC-GLC. Since the mass fragmentography … drug and not on blank serum to which …