Determination of residual fipronil in chicken egg and muscle by LC–MS/MS

• Fipronil residues in chicken egg and muscle were extracted with acetronitrile.
• C18 SPE cartridge was better than common sorbents for purifying fipronil.
• A novel and reliable LC–MS/MS method was established to assay fipronil residue.
• The CCα for fipronil in chicken egg and muscle was 0.002 μg kg−1.

A simple, sensitive and reliable method was developed and applied to the residue analysis of fipronil in chicken egg and muscle by liquid chromatography-tandem mass spectrometry (LC–MS/MS). Chicken egg and muscle samples were extracted with acetronitrile, then salting out by dehydration with anhydrous magnesium sulfate and sodium chloride. The extracts were purified by the C18 solid phase extraction cartridge prior to analysis by LC–MS/MS. The matrix-matched calibration curve showed a good linear within the concentration range from 0.01 to 2.00 μg kg−1 (r2 ≥ 0.999). The average recoveries of fipronil at three spiked levels of 0.01, 0.1 and 1.0 μg kg−1 ranged from 79.7% to 98.0%, and the relative standard deviations were less than 8.8%. The decision limit (CCα) and detection capability (CCβ) of fipronil in chicken egg and muscle matrices were all 0.002 μg kg−1 and 0.01 μg kg−1, respectively. The method has also been successfully applied to monitoring fipronil in the real samples.