IDENTIFICATION OF CLOZAPINE N+-GLUCURONIDE IN THE URINE OF PATIENTS TREATED WITH CLOZAPINE USING ELECTROSPRAY MASS-SPECTROMETRY

Clozapine N+-glucuronide was detected in the urine of five patients chronically treated with clozapine. Identification was made on the basis that the material isolated from urine had the same high-performance liquid chromatographic retention time and positive electrospray mass spectra as that of an authentic reference standard of clozapine N+-glucuronide. These results indicate that electrospray mass spectrometry is a valuable technique in the analysis of low-molecular-weight biologically derived N+-glucuronide metabolites.