A method for residual determination of 5 pyrethroid pesticides in Anoectochilus roxburghii by cloud point extraction-back extraction-GC-MS was established. PEG 6000 was used as extraction agent and isooctane was used for back-extractant. The con- tent was calculated by external standard method. The linear range was from 15 to 2 000 μg x kg(-1) with the good correlation coefficients (0.955-0.999). The recoveries at spiked concentrations of 50-500 μg x kg(-1) ranged from 85.12% to 101.6%. The limit of detection and quantification of 5 pyrethroid pesticides were in the range of 0.63-3.10 μg x kg(-1) and 2.10-10.31 μg x kg(-1), respectively. The proposed method can be applied to the determination of pyrethroid pesticides residues in A. roxburghii.
Chemical Fractionation ; methods ; Gas Chromatography-Mass Spectrometry ; methods ; Orchidaceae ; chemistry ; Pesticide Residues ; analysis ; chemistry ; isolation & purification ; Pyrethrins ; analysis ; chemistry ; isolation & purification