Development and validation of a rapid, sensitive liquid chromatography–tandem mass spectrometry method using electrospray ionization for quantitation of centchroman in rat plasma and its application to preclinical pharmacokinetic study

Liquid chromatography–mass spectrometry method for the quantification of tamoxifen and its metabolite 4-hydroxytamoxifen in rat plasma: Application to interaction study with biochanin A (an isoflavone)

“…The extraction recovery of analytes, through liquid-liquid extraction procedure, was determined by comparing the peak areas of extracted plasma (pre-spiked) standard QC samples (n = 6) to those of the post-spiked standards at equivalent concentrations [18,19]. Recoveries of tamoxifen and 4-hydroxytamoxifen were determined at three concentration levels QC low, QC medium and QC high concentrations viz., 2.5, 80, and 160 ng/mL, whereas the recovery of the IS was determined at a single concentration of 5 ng/mL.…”

“…The effect of rat plasma constituents over the ionization of tamoxifen, 4-hydroxytamoxifen and IS was determined by comparing the responses of the post-extracted plasma standard QC samples (n = 6) with the response of analytes from neat standard samples at equivalent concentrations [18,19]. The matrix effect for tamoxifen and 4-hydroxytamoxifen was determined at three concentration levels viz., 2.5, 80 and 160 ng/mL whereas the matrix effect over the IS was determined at a single concentration of 5 ng/mL.…”

Simultaneous determination and excretion study of six flavonoids in rat after oral administration ofFructus Sophoraeextract by liquid chromatography tandem mass spectrometry

“…When matrix compounds and analytes enter the ion source at the same time, the ionization efficiency of the analyte might be influenced [21]. The matrix effect was evaluated by comparing the peak area responses of postextraction bile and urine blank spiked with analyte to those dissolved in methanol at corresponding concentrations [22,23]. The determination of the extraction recovery and matrix effect of IS were similar to that of analytes.…”

Quantitative determination of formononetin and its metabolite in rat plasma after intravenous bolus administration by HPLC coupled with tandem mass spectrometry

“…The extraction recovery of analytes, through liquid-liquid extraction procedure, was determined by comparing the peak areas of extracted plasma (pre-spiked) standard QC samples (n = 6) to those of the post-spiked standards at equivalent concentrations [21][22][23]. Recoveries of FMN and DZN were determined at three concentration levels QC low, QC medium and QC high concentrations viz., 15, 80, and 180 ng/mL, whereas the recovery of the IS was determined at a single concentration of 100 ng/mL.…”