title: Determination of the new podophyllotoxin derivative NK 611 in plasma by high-performance liquid chromatography with ultraviolet detection.
abstract: A high-performance liquid chromatographic method has been developed for the determination of the new podophyllotoxin derivative NK 611 in plasma samples. A solid-liquid extraction procedure with C18 extraction columns was used for extraction of plasma samples containing NK 611. The adsorbed NK 611 was eluted from the extraction columns with methanol-acetonitrile (50:50, v/v). The elution liquid was injected into a reversed-phase system consisting of a Chrompack C18 column. The mobile phase was acetonitrile-20 mM phosphate buffer, pH 7 (30:70, v/v). The UV detection mode allows sensitive determination of NK 611 in plasma within phase I trials. The limit of detection was 10 ng/ml, the limit of quantitation 35 ng/ml (for 1 ml of extracted plasma and 20-microliters injection volume). The calibration curve is linear within the concentration range 100-1000 ng/ml. The recovery of NK 611 from spiked plasma samples was approximately 80%.
authors.affiliation: Department of Medicine, University Hospital Eppendorf, Hamburg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Hüttmann
authors.forename: K
authors.initials: K
authors.lastname: Mross
authors.forename: D K
authors.initials: DK
authors.lastname: Hossfeld
mesh_terms: D000970:Antineoplastic Agents / Q000097:blood*; D016477:Artifacts; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D015394:Molecular Structure; D011034:Podophyllotoxin / Q000031:analogs & derivatives* / Q000097:blood; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000970:Antineoplastic Agents; C080080:NK 611; D011034:Podophyllotoxin