Simultaneous quantification of centchroman and its 7‐demethylated metabolite in rat dried blood spot samples using LC‐MS/MS

Abstract

An approach has been developed for the quantitative determination of concentrations of centchroman (I), a nonsteroidal once-a-week oral contraceptive, and its major metabolite (7-desmethyl centchroman, II) using dried blood spots (DBS) on paper, rather than conventional plasma samples. The assay employed simple solvent extraction of the DBS sample circle (6 mm) requiring small blood volumes (30 μL) followed by reversed-phase HPLC separation, combined with multiple reaction monitoring mass spectrometric detection. The calibration plot in matrix using d-trans-hydroxy chroman as internal standard (IS) was linear (r² = 0.998) over ranges of 1.5-240 and 4.5-720 ng/mL for I and II, respectively. The recoveries of both I and II were always >60% with quantification limits (signal-to-noise ratio = 10) of 1.5 and 4.5 ng/mL for I and II, respectively. The intra-day and inter-day precision (%RSD) and accuracy (%bias) variations in blood spots for both I and II were better than 13%. Moreover, both I and II were stable in DBS for at least 3 months when stored at room temperature. The developed method was successfully applied to the pharmacokinetic interaction study after oral administration of centchroman with and without co-administration of carbamazepine in female Sprague-Dawley rats using serial sampling and results were comparable with the plasma concentrations reported earlier.

PK–PD Interaction Study of Angiotensin II Antagonist, Losartan, with Selective Estrogen Receptor Modulator, Centchroman

“…In centchroman alone rats, the V d /F and Cl/F were calculated to be 18.7 l/kg and 0.57 l/h/kg, respectively. The appearance of double peak of centchroman, rate of elimination and t 1/2 were comparable, whereas the AUC, Cl/F, V d /F and MRT were comparatively higher with those reported earlier [20,21]. This could be due to monitoring of the drug for a longer period.…”

Simultaneous Determination of Centchroman and Tamoxifen Along with Their Metabolites in Rat Plasma Using LC–MS/MS

“…[4,18,20,[22][23][24][25][26][27][28][29] The ratios of peak areas of analytes to that of IS were found to be linear over a concentration range of 0.2-200 ng/ml for all the analytes. The concentration-(Analyte/IS) area ratio data for centchroman, 7-DMC, tamoxifen and 4-hydroxytamoxifen data fit well with a linear regression model, with weighing of 1/x 2 .…”

“…There is only one method reported for the determination of centchroman along with its active metabolite in dried blood spots, but suffers with lesser sensitivity [24]. Till date, several bioanalytical methods for the determination of tamoxifen in human plasma are reported [4,6,[25][26][27][28].…”

Dried blood spots: Concepts, present status, and future perspectives in bioanalysis

“…Canrenone Neonatal screening LC-MS [73] 13. Centchroman and 7-demethylated centchroman PK and drug-drug interaction study LC-MS/MS [50] 14.…”

“…The proficiency of DBS can reduce the overall clinical trial budget by up to 50%. Lal et al [50] used the DBS method for PK drug-drug interaction study of centchroman and its metabolite with carbamazepine, indicating its applicability in PK drug-drug interaction study. Doping analysis of banned substances can easily be performed with the help of DBS technology.…”