A modified electron-impact GLC-selected ion monitoring mass spectrometric method for captopril is described. Positive chemical ionization GLC-selected ion monitoring and direct chemical ionization confirms the specificity of this procedure for captopril and establishes the chemical ionization techniques as potential analytical methods. This procedure has been adapted to the simultaneous measurement of captopril and its isotopomer. The results of a pilot oral bioavailability study of four subjects receiving either 100 mg of captopril as a direct compression tablet or a solution concomitantly with a 100-mg solution of isotopomer is discussed.
Keyphrases o Captopril-determination in human blood and urine, GLC-selected ion monitoring mass spectrometry, oral coadministration with isotopomer GLC-selected ion monitoring mass spectrometrydetermination of captopril in human blood and urine, oral coadministration with isotopomer 0 Urine, human-determination of captopril in urine blood, GLC-selected ion monitoring mass spectrometry, oral coadministration with isotopomer Captopril (I) is an orally active inhibitor of the angiotensin-converting enzyme (1, 2). A specific determination of I was performed by GLC-selected ion monitoring mass spectrometry (3). The succinimide (Ia) was formed in whole blood by the addition of N-ethylmaleimide (IV), which was then adsorbed onto XAD-2 resin, eluted, methylated, and measured as the ester (Ib). The collaborative studies obtained by the GLC selected ion monitoring