title: Highly sensitive determination of TS-962 (HL-004), a novel acyl-CoA:cholesterol acyltransferase inhibitor, in rat and rabbit plasma by liquid chromatography and atmospheric pressure chemical ionization-tandem mass spectrometry combined with a column-switching technique.
abstract: A quantitative bioanalytical method with excellent specificity using liquid chromatography (LC) atmospheric pressure chemical ionization-tandem mass spectrometry (APCI-MS-MS) combined with a column-switching technique has been developed for the highly sensitive and reliable determination of TS-962 (HL-004), a novel acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor, in rat and rabbit plasma. The method involves protein precipitation of a 25-microl aliquot of plasma sample with eight volumes of methanol containing a deuterium-labeled internal standard, the direct injection of a methanolic supernatant into the analytical instrumentation with no sample evaporation and reconstitution steps, automated on-line clean-up on a C18 short trapping column (10 mm x 4.0 mm I.D.) followed by separation on a C18 analytical column (50 mm x 4.6 mm I.D.), and detection with APCI-MS-MS using m/z 448 ([M+H]+) as a precursor ion and m/z 178 as a product ion in a selected reaction monitoring mode. The lower limit of quantification was 1 ng/ml, and good linearity of the calibration graph was obtained in the range of 1 to approximately 490 ng/ml with excellent reliability. The developed method enabled pharmacokinetic profiles to be determined for rats and rabbits with sequential plasma collection from an individual animal.
authors.affiliation: Drug Metabolism Laboratory, Pharmaceutical Research Laboratories Taisho Pharmaceutical Co., Ltd., Saitama, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Yamaguchi
authors.forename: K
authors.initials: K
authors.lastname: Hachiuma
authors.forename: Y
authors.initials: Y
authors.lastname: Kimura
authors.forename: N
authors.initials: N
authors.lastname: Ogawa
authors.forename: S
authors.initials: S
authors.lastname: Higuchi
mesh_terms: D000081:Acetamides / Q000097:blood*; D000818:Animals; D001274:Atmospheric Pressure; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D004791:Enzyme Inhibitors / Q000097:blood*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D011817:Rabbits; D051381:Rats; D012680:Sensitivity and Specificity; D002785:Sterol O-Acyltransferase / Q000037:antagonists & inhibitors*
chemical_list: D000081:Acetamides; D004791:Enzyme Inhibitors; C401889:TS 962; D002785:Sterol O-Acyltransferase