High-performance liquid chromatographic determination of oxytetracycline residue in cured meat products

The development of a sensitive automated method for residue control of oxyt etracycline (OTC) in cured meat (soudjouk) is described. The principle step s involve the extraction of OTC from cured meat in the presence of citric a cid with nitric acid, methanol and de-ionized water, and then the determina tion Ly HPLC. In HPLC, Hypersil BDC C18 column Nas used and OTC was separat ed at 24 degreesC using a mobile phase of H2O (pH=2.10 with H2SO4): ACN (85 :15, v/v) at a flow rate of 1.5 ml/min. A variable wavelength detector was set at 360 nm. The detection limit of the method was calculated at 8 ng/g a nd the minimum detectable quantity was found as to be 40 mg/ml. The statist ical evaluation demonstrated high absolute recoveries of from 78 to 100% fo r OTC. The method was also used with 10 different cured meat samples market ed in Turkey, and in 7 of them the OTC residue was found to be higher than the tolerance levels accepted by the EU, FDA and Turkish Ministry of Agricu lture.