Assay of Ivermectin Including Determination and Identification of Its Related Substances in Ivermectin Injectable Product by a Stability-Indicating RP-HPLC Method

Ivermectin injectable product is widely used as a parasiticide for the treatment and control of internal and external parasites of cattle and swine. A reversed-phase high performance liquid chromatography (RP-HPLC) method has been developed for the assay of ivermectin, including the determination and identification of its related substances in an ivermectin injectable product. Ivermectin and its related substances are adequately separated using a gradient elution at a flow rate of 1.5 mL/min on a Zorbax Extend-C18 column (150 × 4.6 mm i.d., 3.5 µm particle size) maintained at 30 °C. Mobile phase-A is composed of water and mobile phase-B is composed of acetonitrile/methanol (85/15, v/v). Analytes were monitored by UV detection at 245 nm. The stability-indicating capability of the method has been demonstrated by adequately separating the degradation products from the stress degraded samples of the ivermectin injectable product. The analytical performance of the method was validated as per the current ICH guidelines with respect to specificity, linearity ( R 2 > 0.999), accuracy, precision, detection limit (0.3 µg/mL), quantitation limit (1.0 µg/mL), and robustness. This newly developed HPLC method for assay of ivermectin and determination of its related substances can be used to increase the throughput of a quality control (QC) lab for analytical testing of ivermectin injectable products.