Ionophores are molecules that are used to facilitate transport of ions across cell membranes. Their effectiveness in increasing the permeability of a cell membrane allows ionophores to be used as antibiotics and growth enhancers in various types of animal feeds. The main use of ionophores in poultry feed is as an additive to combat coccidiosis. In cattle feed, it is used to control bacterial populations in the stomach, which promotes better feed efficiency for the cattle. In 1998, the European Union banned use of human-used antibiotics to promote animal growth as resistant bacteria can be transmitted to humans.

The new Euro-Diagnostica Ionophore ELISA is a competetive ELISA designed to detect Salinomycin and Naracin in pet foods and tissues. There is a less than 0.1% cross-reactivity to Monensin and Lasalocid. The limit of detection of the test is 4 parts per billion (ppb) in extracted tissue and 20 ppb in pet foods using a methanol extraction solution.