Improved LC method to determine ivermectin in plasma.

A simple, rapid and sensitive high-performance liquid chromatographic (HPLC) method has been developed to quantify Ivermectin (IVM) in plasma using an isocratic system with fluorescence detection. The method included a fast liquid phase extraction using cold methanol. HPLC separation was carried out by reversed phase chromatography with a mobile phase composed of methanol:acetonitrile:water with 0.2% acetic acid (45:50:5 v/v/v), pumped at flow rate of 2 ml min(-1). Fluorescence detection was performed at 365 nm (excitation) and 475 nm (emission). The calibration curve for IVM was linear from 0.25 to 100 ng ml(-1). The validation method yielded good results regarding linearity, precision, accuracy, specificity and recoveries. The values of the limit of detection (LOD) and limit of quantification (LOQ) were 0.032 and 0.167 ng ml(-1), respectively.