A QuEChERS-based extraction method for the residual analysis of pyraclofos and tebufenpyrad in perilla leaves using gas chromatography: application to dissipation pattern.
The objective of this work was to establish a simple extraction method for the residual analysis of pyraclofos and tebufenpyrad in Perilla leaves. A QuEChERS (quick, easy, cheap, effective, rugged and safe) method was used for extraction using ethyl acetate as an extraction solvent, and cleanup was carried out using dispersive solid-phase extraction technique. The samples were analyzed using gas chromatography with nitrogen phosphorous detector and confirmed by gas chromatography-mass spectrometry. The linearity was excellent (r(2) = 1.0) in matrix-matched calibration for both pesticides. The recoveries at two fortification levels were 80.76-95.38% with relative standard deviation lower than 5%. The limits of detection and limits of quantification were 0.01 and 0.033 mg/kg for both pesticides, respectively. The results revealed that the dissipation pattern of pyraclofos and tebufenpyrad followed first-order kinetics. The pyraclofos and tebufenpyrad residues declined to a level below the maximum residue limits within 14 day between the last application and harvesting. We suggest that pyraclofos and tebufenpyrad could be used efficiently on perilla leaves under the recommended dosage conditions.
Natural Products Chemistry Laboratory, Biotechnology Research Institute, Chonnam National University, Buk-gu Gwangju, Republic of Korea.
M N U
MN
Al Mahmud
Musfiqur
M
Rahman
Tae-Woong
TW
Na
Jong-Hyouk
JH
Park
Angel
A
Yang
Ki Hun
KH
Park
A M
AM
Abd El-Aty
Nilufar
N
Nahar
Jae-Han
JH
Shim
D008401:Gas Chromatography-Mass Spectrometry / Q000191:economics / Q000379:methods*; D016014:Linear Models; D063086:Organothiophosphates / Q000032:analysis* / Q000737:chemistry; D031343:Perilla / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis* / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D011720:Pyrazoles / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D063086:Organothiophosphates; D010573:Pesticide Residues; D010936:Plant Extracts; D011720:Pyrazoles; C429623:4-chloro-N-((4-(1,1-dimethylethyl)phenyl)methyl)-3-ethyl-1-methyl-1H-pyrazole-5-carboxamide; C069547:pyraclofos