Gas chromatographic determination of nitrobenzene in aniline

Hydrogenation of Nitrobenzene to Aniline

Gas-liquid chromatographic determination

A method for the determination of total bile acids in human feces that is suitable for routine application is described and discussed. Bile acids are extracted from freezedried feces with acetic acid and toluene, in the presence of the i?ternal standard 23-nordeoxycholic acid. After saponification of the extract, bile acids and the internal standard are methylated and converted by mild chromic ...

Gas chromatographic determination of deoxynivalenol in wheat.

Modifications to a published method are described for the determination of deoxynivalenol (DON) in wheat by gas chromatography with electron capture quantitation of the heptafluorobutyrate derivative. In the modified method, DON is extracted by shaking the sample with methanol-water on a wrist-action shaker, followed by filtration through rapid flow paper. One concentration step is eliminated, ...

Gas-chromatographic determination of urinary oxalate.

We describe a simple, rapid method for determining urinary oxalate: isolation by precipitation with calcium chloride and conversion to dimethyl oxalate, which then is measured by gas chromatography. To each sample, tracer amounts of 14C-labeled oxalic acid are added, to determine the analytical recovery of urinary oxalate. Analytical recovery of [14C]oxalic acid added to urine specimens ranged ...

Gas-liquid chromatographic determination of nicotine and cotinine in plasma.

We report a procedure for determining nicotine and cotinine in plasma. Nicotine is extracted from 1 ml of plasma with diethyl ether, back extracted, and analyzed by gas-liquid chromatography with a nitrogen/phosphorus detector. Nicotine and its internal standard, modaline, had retention times of 1.9 and 2.9 min, respectively. Cotinine is then extracted from the same plasma with dichloromethane ...