title: [Sensitive determination of vitamin K analogues in biological samples by high-performance liquid chromatography using platinum catalyst reduction and electrochemical detection].
abstract: To investigate the physiological roles of vitamin K analogues in bone metabolism, especially in osteoporosis, we have developed a sensitive and simple analysis system for vitamin K analogues in the serum and bone. After the separation of vitamin K analogues on a reversed-phase column, the analogues were reduced once in a platinum catalyst reduction column on-line and then monitored quantitatively by electrochemical detector (EICOM ECD-300) operated in the oxidation mode (+0.6 V vs. Ag/AgCl). The detection limits at a signal-to-noise ratio of 3 were 2-10 pg for vitamin K analogues. We also investigated the extraction procedures for the vitamin K analogues from serum and bone. Quantitative recoveries from serum and bone were obtained in the range of 80-101% for vitamin K analogues. We could determine both the circulating vitamin K levels in osteoporotic patients and the vitamin K contents in trabecular and cortical bone of osteoarthritis.
authors.affiliation: Department of Biophysical Chemistry, Niigata College of Pharmacy, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Wakabayashi
authors.forename: K
authors.initials: K
authors.lastname: Onodera
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000737:chemistry; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D004563:Electrochemistry / Q000295:instrumentation*; D006801:Humans; D010003:Osteoarthritis / Q000378:metabolism; D010024:Osteoporosis / Q000378:metabolism; D010084:Oxidation-Reduction; D010984:Platinum; D051381:Rats; D012680:Sensitivity and Specificity; D014812:Vitamin K / Q000031:analogs & derivatives* / Q000032:analysis
chemical_list: D014812:Vitamin K; D010984:Platinum