Analysis of flumequine enantiomers in rat plasma by UFLC‐ESI‐MS/MS

Abstract

In this study the analysis and confirmation of flumequine enantiomers in rat plasma by ultra-fast liquid chromatography coupled with electron spray ionization mass spectrometry (using propranolol as an internal standard [IS]) was developed and validated. Plasma samples were prepared by liquid-liquid extraction using methyl tert-butyl ether as the extraction solvent. Direct resolution of the R- and S-isomers was performed on a CHIRALCEL OJ-RH column (4.6 × 150 mm, 5 μm) using acetonitrile / 0.1% formic acid / 1 mM ammonium acetate as the mobile phase. Detection was operated by electron spray ionization in the selected ion monitoring and positive ion mode. The target ions at m/z 262.1 and m/z 260.1 were selected for the quantification of the enantiomers and IS, respectively. The linear range was 0.5-500 ng/mL. The precisions (coefficient of variation, CV%) and recoveries were 1.43-8.68 and 94.24-106.76%, respectively. The lowest quantitation limit for both enantiomers is 0.5 ng/mL, which is sensitive enough to be applied to sample analysis in other related studies.

Enantioseparation and determination of flumequine enantiomers in multiple food matrices with chiral liquid chromatography coupled with tandem mass spectrometry

“…Commercially available enantiopure standards of flumequine were not available, and their elution order on the Chiralpak IC column, which was utilized for chiral separation in our work, has not been reported. The elution order of the flumequine enantiomers was determined according to previous literature, that demonstrated S‐(‐)‐ flumequine was eluted first from the Chiralcel OJ‐RH column . Firstly, we achieved the separation of flumequine under the same condition as depicted by Zhao et al The first eluting peak from Chiralcel OJ‐RH column was collected, then the solvent was evaporated.…”

“…The elution order of the flumequine enantiomers was determined according to previous literature, that demonstrated S‐(‐)‐ flumequine was eluted first from the Chiralcel OJ‐RH column . Firstly, we achieved the separation of flumequine under the same condition as depicted by Zhao et al The first eluting peak from Chiralcel OJ‐RH column was collected, then the solvent was evaporated. The residue was dissolved in methanol and injected into the Chiralpak IC column by optimum condition.…”

“…Nevertheless, a few papers have reported on the enantioselective quantification of flumequine in different matrices, including in rat plasma, sediment, and different water samples. [22][23][24][25] But, to our best knowledge, no literature has been published on enantioselective determination of flumequine in multiple food matrices by LC-MS/MS. Therefore, this study aimed to develop a new robust method for the enantioselective determination of flumequine in multiple matrices (milk, yogurt, honey, egg, chicken, and beef) using a reversed-phase HPLC-MS/MS with the Chiralpak IC column.…”

“…In the present, there is a trend on enantioselective determination of chiral drugs in various matrices. Nevertheless, a few papers have reported on the enantioselective quantification of flumequine in different matrices, including in rat plasma, sediment, and different water samples . But, to our best knowledge, no literature has been published on enantioselective determination of flumequine in multiple food matrices by LC‐MS/MS.…”