title: A validated bioanalytical method in mouse, rat, rabbit and human plasma for the quantification of one of the steroid glycosides found in Hoodia gordonii extract.
abstract: Hoodia gordonii extract contains steroid glycosides, fatty acids, plant sterols and polar organic material. Certain steroid glycosides show appetite suppressant activities following oral ingestion. This study describes the validation of a bioanalytical method for the quantification of one of the steroid glycosides, H.g.-12 (≈ 10% (w/w) of the extract), in mouse, rat, rabbit and human plasma. The method utilises a liquid-liquid extraction with methyl-tert-butyl ether followed by chromatographic separation on a 2.1 × 50 mm C(18) Genesis high performance liquid chromatography (HPLC) column and detection on a triple quadrupole mass spectrometer. Detection of H.g.-12 and its stable isotope internal standards is performed using positive TurboIonspray™ ionisation in multiple reaction monitoring mode. The validation procedure demonstrated assay sensitivity, linearity, accuracy, precision and selectivity over the calibration range of 0.5-150 ng/mL in human plasma (500 μL sample volume), 1.0-100 ng/mL in rat and rabbit plasma (150 μL sample volume) and 1.0-250 ng/mL in mouse plasma (150 μL sample volume) with good recoveries (≥ 77%). H.g.-12 was stable in plasma for ≥ 6 months at -20°C, for up to 4h at ambient temperature (ca22°C) and after 3 freeze-thaw cycles. Plasma extracts were stable for up to 24h at ambient temperature.
authors.affiliation: Phytopharm plc, Lakeview House, 2 Lakeview Court, Ermine Business Park, Huntingdon, Cambridgeshire PE29 6UA, UK. info@phytopharm.com
authors.forename: Weijun
authors.initials: W
authors.lastname: Wang
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Russell
authors.forename: Graeme T
authors.initials: GT
authors.lastname: Clark
authors.forename: Derek
authors.initials: D
authors.lastname: Lewis
authors.forename: Kun Nang
authors.initials: KN
authors.lastname: Cheng
mesh_terms: D000818:Animals; D029062:Apocynaceae / Q000737:chemistry*; D001067:Appetite Depressants / Q000737:chemistry*; D005591:Chemical Fractionation; D002851:Chromatography, High Pressure Liquid; D006027:Glycosides / Q000032:analysis / Q000097:blood*; D006801:Humans; D057230:Limit of Detection; D051379:Mice; D010936:Plant Extracts / Q000097:blood / Q000737:chemistry; D011817:Rabbits; D051381:Rats; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry
chemical_list: D001067:Appetite Depressants; D006027:Glycosides; D010936:Plant Extracts