Determination of Bifenthrin in Tea by Ultra Performance Convergence Chromatography and Gas Chromatography-Mass Spectrometry / 分析化学

ABSTRACT

A method was developed for the determination of bifenthrin in tea by ultra performance convergence chromatography ( UPC2 ) . The samples were extracted with petroleum ether and cleaned up with Waters Sep-PakCarbon NH2 , and then detected by UPC2 . The mobile phase was the mixture of supercritical CO2 and acetonitrile at a flow rate of 1. 5 mL/min. The separation was conducted on a column of ACQUITY UPC2 TM BEH (100 mmí3. 0 mm,1. 7 μm). The UV detector was set at a wavelength of 220 nm. The detection limit was 20 μg/L. The linear range of bifenthrin was 0. 32-10. 30 mg/L. The recoveries ranged from 88. 7% to 98. 2%. The relative standard deviations (RSD) were from 1. 4% to 2. 8%. The result showed that the UPC2 was more efficient, rapid and low-cost than GC-MS. The method can meet the testing requirements of bifenthrin in tea. The efficacy of UPC2 on testing the concentration of bifenthrin in tea was compared with GC-MS based on National Proficiency Testing and the results were satisfactory.