High-performance liquid chromatographic assay for the determination of p-(3,3-dimethyl-1-triazeno)benzoic acid in mouse plasma.
A reproducible and sensitive method is described for assaying p-(3,3-dimethyl-1-triazeno)-benzoic acid (pCOOH-DMT) and for identifying the N-desmethyl metabolite, p-(3-methyl-1-triazeno)benzoic acid (pCOOH-MMT) using high-performance liquid chromatography. The method measures concentrations as low as 1.25 nmol/ml of plasma. Extraction efficiency of internal standard or of added triazenes averages 88% and the coefficient of variation of the method is less than 10%. pCOOH-DMT is stable at room temperature at pH 7.4, whereas pCOOH-MMT undergoes rapid decomposition (half-life 6 min). pCOOH-MMT is more stable in an albumin-containing solution or in plasma, but not in boiled 9000 g mouse liver. After 80 min incubation with a 9000 g mouse liver fraction and reduced nicotinamideadenine dinucleotide phosphate, only 24% pCOOH-DMT was metabolized. Plasma pharmacokinetic studies in mice treated with 200 mg/kg intraperitoneally showed that the potassium salt of pCOOH-DMT has a half-life of 67 min.
D000818:Animals; D000970:Antineoplastic Agents / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004355:Drug Stability; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D007700:Kinetics; D008099:Liver / Q000032:analysis; D051379:Mice; D008810:Mice, Inbred C57BL; D014226:Triazenes / Q000097:blood*
D000970:Antineoplastic Agents; D014226:Triazenes; C030838:1-(4-carboxyphenyl)-3,3-dimethyltriazene