Validation of a confirmatory method of salbutamol in sheep hair by UPLC-MS/MS and its application to pharmacokinetic study

•A new method for determining salbutamol in animal hair was established.•The usefulness of different procedures for extraction of incurred hair were evaluated.•The method was successfully applied to the pharmacokinetic study of sheep hair. A new method for determining salbutamol in hair of sheep by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was established. Samples were extracted with 0.1M of HCl solution. The mixture was heated to 60°C in a water bath and kept at this temperature for 4h. The extracts were purified through SPE method and then dried with nitrogen. Residues were redissolved in mobile phase. The target compound was determined by UPLC-MS/MS with BEH-C18 column. The usefulness and feasibility of different treatment procedures of hair containing salbutamol were evaluated. The range of linearity was 1–100ng/g. The LOD was 0.3ng/g, and the LOQ was 1ng/g. Recoveries were 89–106%, and coefficients of variation were 3.2–13.9%. Pharmacokinetics of salbutamol was studied in healthy sheep after oral administration of 150μg/kg body weight salbutamol for 21 consecutive days. Salbutamol residues in hair were still detected after 21 days of administration.