TRIMETHYLSILYL-O-METHYLOXIME DERIVATIVES FOR THE MEASUREMENT OF [6,6-H-2-(2)]-D-GLUCOSE-ENRICHED PLASMA SAMPLES BY GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

A new method for the determination of the enrichment of [6,6-H-2(2)]-D-glucose in human plasma by gas chromatography-mass spectrometry (GC-MS) is described. (2,3,4,5,6)-Pentakis-O-trimethylsilyl-O-methyloxime-D-glucose is used as a derivative for the GC measurement. Using GC-MS with electron-impact ionization, the enrichment is measured in the single-ion monitoring mode observing the masses m/z 319 and 321. In contrast to other methods the use of this glucose derivative reduced the amount of plasma needed from 200 to 10-mu-l and no chemical ionization equipment is needed for the mass spectrometer.