Mohammad Alimoradi - Faculty of Chemistry, Islamic Azad University, Arak, Iran
Saeed Kochaki - Islamic Azad University Arak Branch, Arak, Iran

A fast, simple, and sensitive sample preparation procedure based on dispersive liquid–liquid micro extraction (DLLME) is proposed for the determination of tylosinA (antibiotic drug) in milk samples using high performance liquid chromatography (HPLC) and UV detection. The influence of several important parameters on extraction efficiency of tylosin was evaluated. Under optimized conditions, a linear relationship was obtained between the peak area and the concentration of tylosin in the range of 0.02–0.1μg l-1. The detection limits were 0.03 μg l-1. Intra-day and inter-day precisions for the analysis of tylosin were in the range of 0.9–2.7% with recovery 63-108%. In solid phase extraction (SPE) for the determination of tylosinA in milk samples using high performance liquid chromatography (HPLC) and UV detection Under optimized conditions, The detection limits were 0.08 μg l-1 with precisions for the analysis of tylosin were in the range of 1–3.2% with recovery 62.8-76%. Thus the result show (DLLME) is sensitive and high recovery than SPE. This extraction method (HPLC-DLLME) applicability for the determination of tylosin in milk, animals food, animal meats.