DIN EN 16930:2017-10

DIN EN 16930 specifies a high performance liquid chromatographic – UV detection (HPLC-UV) method for the simultaneous determination of two growth promoters Carbadox and Olaquindox contents in compound feeds and raw materials at levels ranging from the limit of quantification to 100 mg/kg. The limit of quantification of the method has been demonstrated to be lower than 3 mg/kg for olaquindox and 4 mg/kg for carbadox. The two growth promoters are extracted from the sample with a mixture of methanol and water 1:1, v:v. The extract of animal feeds is purified through a short open glass aluminium oxide column or by an alumina Solid Phase Extraction (SPE). The final extract is analysed by reversed phase HPLC with UV detection at a wavelength of 375 nm. Alternatively, for confirmation purposes, a Diode Array Detector (DAD) can be used. The presence of furazolidone can interfere with the determination of carbadox. If a DAD is used, many other veterinary drugs or feed additives can be detected (ronidazole, meticlorpindol, nitrofurazone, dimetridazol, furaltadon, sulphonamides, etcetera) but their signals do not interfere with the target ones. In some special feeds, matrix interfering peaks may be present, very close to the carbadox peak. The standard has been prepared by CEN/TC 327 "Animal feeding stuffs - Methods of sampling and analysis", the secretariat of which is held by NEN (Netherlands). The responsible German standardization committee is Working Committee NA 057-03-03 AA "Futtermittel" ("Animal feeding stuffs") at DIN Standards Committee Food and Agricultural Products (NAL).