Differential pulse polarographic determination of plasma menadione

✍ Scribed by Steven A. Akman; Fumiyo Kusu; Kiyoko Takamura; Rowan Chlebowski; Jerome Block

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 492 KB
• Volume: 141
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(84)90075-7

✦ Synopsis

A differential pulse polarographic assay for plasma vitamin K, (menadione) has been developed. Details of the assay are (i) lipid-soluble material is extracted from plasma into ether by the method of Bjomsson ef al. [( 1978) Thromb. Haemostas. 2, 466-4731; (ii) ether is evaporated under nitrogen and the residue is dissolved in the supporting electrolyte, methanol: 0.2 M borate buffer (9:1), pH 6.8; (iii) current height is measured at -0.32 V vs 8CE on the differential pulse polarogram. The lower sensitivity limit of this technique after addition of standard vitamin Ks to plasma is 0.3 pM; the calibration curve is linear from 0.6 through 10 pM. Two patients treated with a single dose of menadiol sodium diphosphate, 20 m&M* i.m., achieved measurable plasma vitamin K3 levels at 0.5 to I.0 h ranging between 0.5 (0.08 &ml) and 2 PM (0.3 &ml).