Development and validation of UHPLC method for the determination of fluazuron in bovine tissues

Abstract

Context: Fluazuron is an arthropod growth regulator drug for the control and treatment of parasitic infection in bovines by Rhipicephalus (Boophilus) microplus, one of the most important parasites for livestock due to the great economic losses. Aims: To quantitative and confirmatory ultra-high-performance liquid chromatography with ultraviolet detection (UHPLC) method was developed to determine fluazuron in bovine tissues (muscle, fat, liver, and kidney) to assess drug residues. Methods: Tissue samples were extracted with liquid phase extraction performed with acetonitrile. The chromatography (UHPLC) was performed using a C18 column (100 Å, 5 μm, 4.6 × 250 mm) maintained at 37°C. The mobile phase consisted of acetonitrile:water 65:35 v/v with a flow rate of 1.0 mL/min. The UV wavelength was set at 260 nm, and the injection volume was 100 μL for all worked tissues (injection site, muscle, fat, liver, and kidney). Results: Validated analytical method exhibited a linear relationship over the range of 50–800 ng/g for muscle, including injection site, 125–2000 ng/g for kidney and liver, and 1750–28000 ng/g for fat, with a coefficient of determination greater than 0.99 in all cases. The lower limit of quantification (LLOQ) of fluazuron in muscle and injection site samples was 50 ng/g with a coefficient of variation (%CV) of 6.40%. The recovery percentage for fluazuron was greater than 75% in all the target tissues. Conclusions: The extraction, separation, and quantification UHPLC method was valid to determine fluazuron in bovine tissues as well as for studies of drug residues in these animals.