A thin-layer chromatographic method for the detection of tylosin in biological materials and feeds

Abstract

The detection of the antibiotic tylosin by means of a thin-layer chromatographic technique is described. Identification is made under UV light and by spraying the chromatoplates consecutively with acid iodoplatinate, Dragendorff's reagent and a saturated solution of silver sulphate in 10% sulphuric acid. The sensitivity for the three consecutive sprays lies between 2 and 4 μg of tylosin base. The best extraction was obtained with a mixture of chloroform-ethyl acetate (2:1). These extraction and chromatographic techniques were applied to the isolation and detection of tylosin from biological materials. Because of the disturbance by the proteins present in blood plasma, tissue homogenates and milk, deproteinization must be performed before extraction. For feeds, urine and tissue homogenates, two-dimensional chromatography was preferred. Tylosin could be detected with accuracy at concentrations of 2–4 p.p.m. in these different materials. This method was also applied to the detection of tylosin in biological fluids such as blood plasma, urine and milk after injection in healthy cows and passage through the body.