Validation of an LC-MS/MS method for the quantitative determination of a novel fungicide: pyraoxystrobin in rat plasma and its application to a toxicokinetics study

A simple, sensitive, and reliable liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for determination of pyraoxystrobin in rat plasma and applied to a toxicokinetics study. The separation was performed by gradient elution on a Luna 5 μ C18 (2) 100 Å column (50?×?4.6 mm I.D., 5 μm) with mobile phase: water (0.1 % formic acid, v/v)/acetonitrile (0.1 % formic acid, v/v), followed by quantification with a mass detector in multiple reaction monitoring (MRM) mode using ESI as an interface. The calibration curve was linear over a concentration range of 1.00–200 ng/mL. The recovery for pyraoxystrobin ranged from 101.4 to 108.2 %. The intraday bias and precision ranged from ?9.3 to 8.1 % and from 0.7 to 8.4 %, respectively, and the interday bias and precision ranged from ?0.3 to 4.0 % and from 4.4 to 7.2 %, respectively. The toxicokinetics of pyraoxystrobin after single 100 and 1,000 mg/kg oral doses were studied in rats. Figure

The chromatogram of pyraoxystrobin highest calibration standard (ULOQ) extract.