HIGHLY SENSITIVE LC-MS/MS METHOD FOR THE DETERMINATION OF CLOZAPINE IN RAT PLASMA: APPLICATION TO A PRECLINICAL PHARMACOKINETIC STUDY

Abstract

A highly sensitive, rapid assay method has been developed and validated for the quantification of clozapine in rat plasma using LC-MS/MS. The extraction process involved plasma protein precipitation with acetonitrile and elution with a mobile phase constituted by acetonitrile and acidic water (80/20), at 0.8 mL/min flow rate (split 1:3). Chromatographic separation was performed by C18 Symmetry column (4.6 × 75 mm, 3.5 µm). The lower limit of quantification was 1 ng/mL and the linearity was observed between 1–1000 ng/mL with a determination coefficient >0.9810. The intra- and inter-day precisions were less or equal to 8.38 and 4.36%, respectively. The method showed sensitivity, linearity, precision, accuracy, and specificity necessary for quantification of plasma clozapine in preclinical pharmacokinetics studies.

Keywords:

• clozapine
• LC-MS/MS
• pharmacokinetics
• preclinical studies
• quinine
• rat plasma

ACKNOWLEDGMENT

The author acknowledges CNPq/Brazil for individual grants and financial support.

Notes

^a mean of six replicates at each concentration.

^b mean of eighteen replicates at each concentrationRSD, relative standard deviation (SD × 100/mean).

*n = 3; **mean of three samples.