The Detection of Tramadol in Honey

Tramadol is a centrally acting analgesic selective for the μ-opioid receptor with antidepressant and dopamine releasing actions. In Egypt, dependence on and abuse of tramadol presents a challenging health problem and the drug is included in the narcotic analgesic schedule III. In this study, a sample of commercially available honey was brought to the laboratory of narcotics and poisons on the suspicion of withdrawal symptoms upon discontinuation. The presence of tramadol was suspected and the sample was subjected to thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Liquid-liquid extraction was carried out using a mixture of chloroform and isopropanol (4:1, v/v)(3:1) in an alkaline medium (pH 8.5). The re-constituted residue was spotted on a TLC plate along with standard tramadol and sprayed with Dragendorff’s reagent. Honey samples were found positive for tramadol. Determination of tramadol was then carried out using HPLC. Separation was achieved on ODS-reversed phase column (C18, 25 x 0.46 cm i.d.5 μm).the mobile phase consisted of water/acetonitrile/triethylamine 40/60/0.1 v/v and was delivered at a flow rate of 2 ml/min. UV detection was performed at 280 nm, and the injection volume was 20μL. HPLC indicated the presence of tramadol HCl in honey. The concentration of tramadol in the sample was determined by an external standard method using peak area. The concentration of tramadol in the sample was then found to be 36.5 mg/ml. The present study is the first which describes the identification of tramadol in commercial honey.