This study was aimed to develop an optimized and rapid multi-residue method using gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) in brown rice, orange and spinach. Shimadzu GC/MS-TQ8040 was used for analysis 360 compounds in one run. To analyze many numbers of pesticide, a variety of instrumental conditions (choice of liner, high pressure injection, inlet temperature, dwell time, etc.) were optimized. To achieve the better separation and the reduced analysis time, a short (20-m) and narrow microbore (0.18 μm) column was selected. The priming effects on liner were tested to reduce matrix effect and optimization of the sample preparation was performed through preliminary tests such as extraction solvent, buffering salts and clean-up sorbents in representative crops. The target analytes were extracted with acidified acetonitrile and partitioned with magnesium sulfate and sodium chloride. The dispersive solid phase extraction procedures were carried out with extracts before the analysis of GC-MS/MS without filtering procedure. Quantification of each analyte was performed by plotting matrix matched calibration curves at concentration ranging from 0.0025 to 0.1 mg/kg. Correlation coefficients (R<sup>2</sup>) of calibration curves were &gt;0.99 for most of target compounds. Limit of detection and limit of quantitation was estimated by signal to noise ratio of 3 and 10. To evaluate validity of the method developed in this study, recovery tests were carried out with untreated organic samples at spiking levels of 0.01 and 0.05 mg/kg (n=6). Under the developed optimized conditions, most of the pesticides satisfied the recovery criteria of 70-120% (RSD ≤20%). As a result, the optimized method was proved to be efficient and suitable for analyzing a large number of GC amendable pesticide residues analysis in rapid and simultaneous manner.

Optimization and validation of 360 pesticides multiresidue method for GC-MS/MS in brown rice, orange and spinach

253rd National Meeting (2017)

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