Development and validation of an automated extraction method (accelerated solvent extraction) and a reverse-phase HPLC analysis method for assay of ivermectin in a meat-based chewable formulation.

A new method for monitoring ivermectin content in HEARTGARD CHEWABLES has been developed and validated. The method consists of the automated extraction of ivermectin from the meat-based formulation under conditions of elevated temperature and pressure (accelerated solvent extraction, ASE, and determination of the active by reverse-phase high performance liquid chromatography (HPLC). The method resolves both active species of ivermectin (components H(2)B(1a) and H(2)B(1b)) from the formulation matrix.