title: Determination of the alkyl lysophospholipid derivative ET-18-OCH3, a new antineoplastic drug, in plasma.
abstract: We describe a sensitive method for measuring the concentration of the new antineoplastic drug ET-18-OCH3 in plasma. After plasma lipids are extracted, ET-18-OCH3 is separated from the excess of endogenous lipids by thin-layer chromatography and specific enzymatic hydrolysis of sphingomyelin by the action of sphingomyelinase. Analytical recovery after the complete isolation was 73.5% (CV = 9.8%, n = 15). [3H]-ET-18-OCH3 is used as internal standard. A densitometric method in which 8-anilino-1-naphthalenesulfonate, Mg salt, is used as fluorescent agent (excitation at 367 nm and emission greater than 390 nm) allows the sensitive determination of ET-18-OCH3 down to 0.1 mg/L (CV greater than 30%). The day-to-day CV is 25% for concentrations of 0.15 to 0.625 mg/L, 12% for 1.5 to 5.0 mg/L. Preliminary pharmacokinetic data reveal gastrointestinal absorption of ET-18-OCH3 after multiple oral administration.
authors.affiliation: Institut für Pharmazeutische Chemie, Westfälische Wilhelms-Universität, Münster, F.R.G.
authors.forename: H G
authors.initials: HG
authors.lastname: Schaefer
authors.forename: P
authors.initials: P
authors.lastname: Rohdewald
mesh_terms: D000284:Administration, Oral; D000970:Antineoplastic Agents / Q000097:blood*; D002855:Chromatography, Thin Layer; D003720:Densitometry / Q000379:methods; D006801:Humans; D010742:Phospholipid Ethers / Q000097:blood* / Q000493:pharmacokinetics; D010743:Phospholipids / Q000302:isolation & purification; D013109:Sphingomyelins / Q000097:blood; D013223:Statistics as Topic
chemical_list: D000970:Antineoplastic Agents; D010742:Phospholipid Ethers; D010743:Phospholipids; D013109:Sphingomyelins; C026659:edelfosine