Mass fragmentographic determination of pyrazinamide and its metabolites in serum and urine.
A combined gas chromatographic-mass spectrometric technique is described for the simultaneous determination of pyrazinamide and its two main metabolites, pyrazinoic acid and 5-hydroxypyrazinoic acid. Serum (200 microliter) is deproteinized and evaporated to dryness; urine (20 microliter) is evaporated. The crude residues are silylated and selected ions are monitored in the chemical-ionization mode with isobutane as both chromatographic carrier and reagent gas. The sensitivity is 10 ng/ml for pyrazinamide and pyrazinoic acid and 20 ng/ml for the 5-hydroxy metabolite in a single analysis. Nicotinic acid and nicotinamide are internal standards. Both unchanged drug and metabolites were identified and quantified in the serum and urine of human subjects.
D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008722:Methods; D011718:Pyrazinamide / Q000032:analysis* / Q000097:blood / Q000378:metabolism / Q000652:urine / Q000031:analogs & derivatives; D011719:Pyrazines / Q000032:analysis* / Q000097:blood / Q000652:urine
D011719:Pyrazines; D011718:Pyrazinamide; C005296:pyrazinoic acid