Method development for the determination of sulfonylurea herbicides residue in rice using liquid chromatography-mass spectrometry

Abstract

Sulfonylurea herbicides (SUHs) are widely used for controlling weeds in paddy. The residue of these herbicides may contaminate to rice. Thus, an analysis of Sulfonylurea herbicide residue was conducted. A determination method of Sulfonylurea herbicides was developed and validated seven compounds. Trace determination level was based on liquid liquid extraction and followed by solid phase extraction as a sample preparation step. Octadecyl (C18) was coupled with aminopropyl (NH[subscript 2]) cartridge which isolated and cleaned up the analytes from the rice sample. Liquid Chromatography/Mass Spectrometry was optimized and developed for multiresidual analysis of seven sulfonylurea herbicides. Reversed-phase LC/ESI/MS in positive ion modes was used to separation and analysis. MS data acquisition was performed by selected ion monitoring (SIM) mode. The average recoveries of seven compounds were 79-131% in the rice sample. Method detection limits and method quantitation limits were reduced to 0.91 and 1.55 ppb, respectively. Method validation was studied in an organic rice sample. Linearity for quantitative analysis was shown a linear dynamic range 1.00 to 100 ppb. The accuracy and intra- and inter-day precision were reported in an acceptable range. Method robustness was developed from the method Placket-Burman Experimental Design.