Gas chromatographic determination and gas chromatographic-mass sepectrometric analysis of chloramphenicol, thiamphenicol and their metabolites.

A rapid and accurate gas chromatographic (GC) method is described for the determination of chloramphenicol, thiamphenicol and their metabolites excreted in human urine. These excretions were pre-treated with diazomethane and N,O-bis(trimethylsilyl)acetamide, so that they could be easily subjected to GC with satisfactory separation from each other and also from other urinary excretions, and could be determined simultaneously. The structures of the metabolites were confirmed by GC combined with mass spectrometric measurements of the GC peaks. The application of the method to urine specimens enabled more precise results for the amounts of metabolites present to be obtained; the excretion of thiamphenicol glucuronide was not observed.