Development and Validation of an HPLC Method for the Simultaneous Determination of Fipronil, Chlorfenapyr, and Pyriproxyfen in Insecticide Formulations

In this study, the analytical method development and validation of an HPLC assay for simultaneous determination of fipronil, chlorfenapyr, and pyriproxyfen in formulation products is described. On the basis of solubility and chromatographic separation with good resolution, acetonitrile water (80+20) was selected as the mobile phase in isocratic mode with a flow rate of 1 mL/min. Chromatographic separations were performed on a Beckman C18 analytical column (4.6 mm x 15 cm, 5 pm particle size; Musa Jee & Sons, Karachi, Pakistan). The retention times for fipronil, chlorfenapyr, and pyriproxyfen were 3.70, 8.61 and 10.09 min, respectively. Calibration curves of all studied insecticides were linear in the concentration range of 20 to 800 pg/mL, with R2>0.997. The LODs of fipronil, chlorfenapyr, and pyriproxyfen were 15.1, 13.3, and 20.0 pg/mL, respectively, whereas the LOQs were 45.9, 40.3, and 60.6 pg/mL. Interday precision was RSD, %<2 for all formulation types, whereas intraday precision was <3. The accuracy of the proposed method was determined by interlaboratory comparison. The z-score for all formulation results were <2.The proposed method is low-cost, green, accurate, and precise and can suitably be used for the simultaneous quantitative determination of fipronil, chlorfenapyr, and pyriproxyfen in their formulations.