title: Liquid chromatography-mass spectrometry assay of a thiadiazole derivative in mice: application to pharmacokinetic studies.
abstract: Modern atmospheric pressure ionization (API) ion-trap mass spectrometry in connection with fast chromatographic separations using a short narrow-bore C8 column was developed to determine 5-phenyl-3-thioureido-1,2,4-thiadiazole (301029), a novel virus inhibitor in serum. Both 301029 and an internal standard (I.S.) were separated from serum samples by acetonitrile deproteinization and extraction without time-consuming reconstitution. The chromatographic separation was achieved on a C8 reversed-phase narrow-bore column using acetonitrile-water-acetic acid (90:10:0.01, v/v/v) as a mobile phase. The mass spectrometric analysis was performed by atmospheric pressure chemical ionization (APCI) mode with positive ion detection. Single ion monitoring (SIM) scan mode of m/z 237 and 158 was used to quantitatively determine 301029 and I.S., respectively. The low limit of quantitation was 25 ng/ml. The assay exhibited a linear range of 25-2500 ng/ml. Recovery from serum proved to be 100-113%. The precision (C.V.) and accuracy (RE) of the method were 2-12% and 94-112%, respectively. The present method was applied to determine the pharmacokinetic parameters of 301029 following oral administration of the agent to mice at 5 g/kg. The results revealed that the elimination half-life of 301029 was 413 min and the area under serum concentration-time curve was 354 microg/ml/min.
authors.affiliation: Institute for Drug Development/CTRC, San Antonio, TX 78245, USA.
authors.forename: H
authors.initials: H
authors.lastname: Wong
authors.forename: L
authors.initials: L
authors.lastname: Jia
authors.forename: J B
authors.initials: JB
authors.lastname: Camden
authors.forename: S D
authors.initials: SD
authors.lastname: Weitman
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000097:blood* / Q000493:pharmacokinetics; D019540:Area Under Curve; D002853:Chromatography, Liquid / Q000379:methods*; D006207:Half-Life; D013058:Mass Spectrometry / Q000379:methods*; D051379:Mice; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013830:Thiadiazoles / Q000097:blood* / Q000493:pharmacokinetics
chemical_list: C453399:5-phenyl-3-thioureido-1,2,4-thiadiazole; D000998:Antiviral Agents; D013830:Thiadiazoles