Abstract
A sensitive, specific, and rapid liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method for the determination of dapsone, chlorproguanil, and their metabolites was developed and validated over a concentration range of 2–2000 ng/mL using 200 µL of plasma. After a simple solvent precipitation procedure, the supernatant was analyzed directly by HPLC-MS/MS method using an XTerra RP18 (2.1 mm × 100 mm, 5.0 µm) column with mobile phase consisting of acetonitrile-0.1% formic acid in water (75:25, v/v, pH 3.0) in an isocratic mode at a flow rate of 0.3 mL/min. Mass detection was performed using a triple quadrupole mass spectrometer operating in positive electrospray ionization mode. The elution of chlorproguanil (CPG, 288 ->204), chlorcycloguanil (CCG, 286 ->229), dapsone (DDS, 249 ->156), monoacetyldapsone (MADDS, 291 ->156), and trimipramine-D3 (TMP-D3, 298 ->103) was monitored using multiple reaction monitoring. The lower limit of detection for CPG, CCG, DDS, and MADDS was 0.5 ng mL−1 while the limit of quantification was 2 ng mL−1 in human plasma. The extraction recovery of CPG, CCG, DDS, MADDS, and TMP-D3 from human plasma was higher than 87%. The method may find its application in therapeutic monitoring of these compounds in biological matrix.
ACKNOWLEDGMENT
The authors sincerely acknowledge the financial support from Uttarakhand State Council for Science and Technology, Uttarakhand to perform this study.
Notes
*Precision [RSD (%)] = (SD/mean) × 100.
**Accuracy (%) = (mean measured concentration/nominal concentration) × 100.
IS* = Internal Standard.
Note. All QC samples were analyzed in triplicate. Mean values are reported.
Obs. = observed; Dev. = deviation.