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Simultaneous determination of ginkgolide A, B, C, bilobalide and rutin in rat plasma by LC-MS/MS and its application to a pharmacokinetic study

Hu Bingying, Sun Yingying, Wang Min, He Zhisheng, Chen Shanshan, Qi Dake, Ge Zhen, Fan Lingling, Chen Jingfang, Wei Yang

Acta Chromatographica

2022

Vol. 34, no. 4

386--393

A reliable LC-MS/MS method for the determination of five bioactive constituents (bilobalide, BLL; ginkgolide A, GLA; ginkgolide B, GLB; ginkgolide C, GLC; rutin) of Ginkgo biloba leaf extracts (GBE) in rat plasma was established, fully validated and applied to an intragastric pharmacokinetic study of a preparation of GBE in rat. Samples were extracted with ethyl acetate. C18 column was selected as analytical column in this method. Mobile phase was water with 0.01% formic acid and acetonitrile. Quantification was performed in negative multiple-reaction monitoring mode. Matrix instability of terpene lactones was noticed and hydrochloric acid was used as a stabilizer. This method showed good precision and accuracy, recovery was reproducible and matrix effect was negligible. Among four terpene lactones, BLL had the highest exposure and the shortest terminal half-life, GLA and GLB had lower exposure and longer terminal half-life, the exposure of GLC was lowest and its terminal half-life was the maximum, and all of them showed rapid absorption. This study provides a reference for determination of terpene lactones and flavonol glycoside prototypes in GBE and offers pharmacokinetic data of flavonol glycoside prototype in GBE.

Hollow fiber-based liquid phase microextraction combined with high performance liquid chromatography for determination of flavonoids in Ginkgo biloba and urine

Lu H., Wang X., Liu X., Jiang S.

Chemia Analityczna

2009

Vol. 54, No. 3

309-319

A hollow fibre membrane-based liquid phase microextraction (HF-LPME) method for determination of flavonoids in Ginkgo biloba leaves was developed. Three flavonoids: quercetin, kaempferol, and isorhamnetin were extracted and then analysed by high performance •-:; liquid chromatography. The factors affecting HF-LPME, including concentration of donor ,; and acceptor phases, concentration of NaCl, extraction time, and stirring speed were systematically investigated. Under the optimum conditions, calibration plots of reasonable linearity were constructed in the analyte's concentration range of 10-100 μg L-1. Up to 200-fold enrichment factor for quercetin and up to tens of folds for kaempferol and isorhamnetin ' were obtained. The method was applied to determine the concentrations of flavonoids in urine and was proven to be an convenient sample preparation technique.

Opracowano metodę oznaczania flawonoidów w liściach Ginkgo biloba za pomocą ^ mikroekstrakcji z fazy ciekłej przy użyciu membranowego wydrążonego włókna. Ekstra-howano i analizowano trzy flawonoidy: kwercetynę, kempferol i izorhamnetynę stosując wysokosprawną chromatografię cieczową. Systematycznie zbadano następujące czynniki wpływające na mikroekstrakcję: stężenie donora i akceptora, stężenie NaCl, czas ekstrakcji oraz szybkość mieszania. W optymalnych warunkach uzyskano liniowy wykres krzywej kalibracji w zakresie stężenia analitu od l O do 100 μg L-1. Współczynnik zatężenia wynosił do 200 razy w przypadku kwercetyny i do dziesiątek razy w przypadku kempferolu oraz izorhamnetyny. Opracowaną metodę zastosowano do oznaczania zawartości flawonoidów w moczu. Stwierdzono, że metoda jest odpowiednia do przygotowywania próbek.