Animal health products and feed additives are being used to increase production efficiency as demand for livestock and fishery products increases. Tetracyclines are currently approved for some applications because of their excellent properties. However, the Food Sanitation Law sets a maximum allowable daily intake for food safety. In May 2006, the maximum residue limits for livestock and fishery foods were established in line with the introduction of a positive list system.
In this application the established test method was used to extract samples with a citric acid buffer containing EDTA, remove lipids with hexane, purify with styrene-divinylbenzene copolymer, and measure by HPLC.