Polyether antibiotics, such as Monensin, Narasin, and Salinomycin, in raw material, premix, liquid supplements, and final feeds, are best quantified using a high-performance liquid chromatograph equipped with a post-column reactor. The polyether antibiotics react, post-column, with Vanillin in the presence of Sulfuric acid, and the resulting products can be detected at 520 nm. However, this corrosive reagent can adversely degrade most instruments. Pickering’s special Post- Column Systems, comprised of non-metallic parts and washing pump head, offers resistance to sulfuric acid. Special operating instructions will also be included with this instrument. Contact Pickering Laboratories for more information about the Inert Vector PCX Post-Column System for polyether antibiotics.