Development and validation of a rapid selective high-throughput LC-MS/MS method for the determination of triclabendazole sulfoxide concentrations in sheep plasma and its use in bioequivalence studies

Abstract

Triclabendazole is one of the main drugs used to treat liver fluke in livestock. A rapid LC-MS/MS method was developed and validated to determine ovine plasma levels of triclabendazole sulfoxide. A Gemini NX-C18 column was used to achieve analytical separation, with gradient elution of a mobile phase composed of 0.1% formic acid in acetonitril and 0.1% formic acid in water at flow rate of 0.6 mL/min. MRM with positive ESI ionization was used for the detection of triclabendazole sulfoxide (m/z 360.10 from m/z 376.97). Fenbendazole was used as internal standard. Plasma protein precipitation with acetonitrile was used for sample processing. The method was validated with regards to selectivity, linearity (r > 0.9939), within run and between run precision (CV < 8.9%) and accuracy (bias < 8.9%) over the concentration range 1-100 μg/mL plasma. The method developed is simple, selective and can be applied in bioequivalence and bioavailability studies.