Abstract: new method has been developed for the simultaneous determination of diflubenzuron and triflumuron residues in greasy wool by reversed-phase high performance liquid chromatography (HPLC). The pesticides were extracted by hexane-ether from greasy wool and cleaned up with gel permeation chromatography (GPC) and solid phase extraction (SPE). The pesticides were analyzed by HPLC-diode array detector (DAD) and quantified by external standard method. The linear ranges of diflubenzuron and triflumuron were 0.41-41 mg/L and 0.38-38 mg/L, and the correlation coefficients were 0.9996 and 0.9999, respectively. The limits of detection were 0.22 mg/kg for diflubenzuron and 0.18 mg/kg for triflumuron; the limits of quantification were 0.73 mg/kg for diflubenzuron and 0.60 mg/kg for triflumuron. The average recoveries of pesticides spiked levels from 0.76 to 10.25 mg/kg in greasy wool samples were in the range of 86.3%-96.7%, and the relative standard deviations were 4.2%-8.7%. The method developed shows little interferences, good recovery and repeatability. It is suitable for the simultaneous determination of diflubenzuron and triflumuron in greasy wool samples.

Key words: diflubenzuron, greasy wool , high performance liquid chromatography (HPLC), solid-phase extraction (SPE), triflumuron, gel permeation chromatography (GPC)