Determination of bromhexine and its metabolites in equine serum samples by liquid chromatography – Tandem mass spectrometry: Applicability to the elimination study after single oral dose

摘要: Bromhexine (BH), expectorant used in the treatment of respiratory disorders associated with viscid or excessive mucus, is not permitted for use competing horse by many authorities horseracing and Olympic disciplines. Metabolic studies are great importance anti-doping field because they allow updating selection most appropriate markers prohibited substances, such as metabolites present at higher concentration levels and/or lasted a longer period time biological samples than parent drug. This study describes LC-MS/MS-based method simultaneous determination BH its metabolites, including 4-(2-amino-3,5-dibromobenzylamino)cyclohexanol (4-HDMB), 3-(2-amino-3,5-dibromobenzylamino)cyclohexanol (3-HDMB), equine serum samples. The 2-(2-amino-3,5-dibromobenzylamino)cyclohexanol (2-HDMB) was monitored well. assay validated terms linearity (R² greater than 0.9951), intra- inter-assay accuracy (91.6 – 109.1%) precision (CV < 9.6%) well recovery (94.8 105.65%). LODs were 0.0052, 0.0053, 0.0056 0.0043 ng/mL BH, 2-HDMB, 3-HDMB 4-HDMB, respectively. developed applied to determine curses concentrations collected 95.25 h following single oral administration two healthy mares (in dose 0.8 mg/kg). drug found (major metabolite) 4-HDMB (minor metabolite), however, both Thus, can be considered abuse markers.