Cm. Chavez et al., DETERMINATION OF PIRENZEPINE IN HUMAN PLASMA USING LIQUID-CHROMATOGRAPHY WITH TANDEM MASS-SPECTROMETRIC DETECTION, Journal of pharmaceutical and biomedical analysis, 13(9), 1995, pp. 1179-1184
A sensitive (LOQ = 1 ng ml(-1)) and specific method based on liquid ch
romatography with tandem mass spectrometric (MS/MS) detection has been
developed and validated for the analysis of pirenzepine (I) in plasma
. Sample preparation involved liquid-liquid extraction of drug and int
ernal standard (IS) from basified plasma. The organic extract was evap
orated to dryness, and the residue was reconstituted in the mobile pha
se and then injected into the liquid chromatography/MS/MS system. Drug
, IS, and endogenous impurities were separated using reverse-phase chr
omatography. A Sciex API III tandem mass spectrometer equipped with a
heated nebulizer was operated in the positive ion mode. Multiple react
ion monitoring using the parent-->daughter ion combinations of mit 352
-->113 and 629-->422 was used to quantify I and IS, respectively. The
method was validated in the concentration range of 1-100 ng ml(-1) pla
sma with adequate assay precision and accuracy, and was utilized to su
pport human safety and tolerability study with I.