Kyung-Ae Son

Development and Validation of a Quick Easy Cheap Effective Rugged and Safe-based Multi-residues Analysis Method for Persimmon, Grape and Pear using Liquid Chromatography-tandem Mass Spectrometry

Association of official agricultural chemists official method was adapted and used to develop analytical method for determination of 76 pesticides residues in persimmon, grape, and pear by concurrent use of liquid chromatography-tandem mass spectrometry. Despite few exceptions in particular matrix, two fortified spiking (100 and 400 ppb) in three matrices gave satisfactory results in terms of accuracy, repeatability, precision, and linearity. Method detection limits (MDLs) were determined using five low spiking and eight replicate samples. MDLs were calculated by multiplying the standard deviation with student t-value 2.998 for n-1 (7) degree of freedom at 99% confident level. limit of quantification were obtained by multiplying standard deviation with 10. Experimental results indicate grape was the most problematic matrix among tested fruits and persimmon the least. Etoxazole is the most problematic pesticide and not applicable in this method. Developed method was successfully applied for the determination of residual pesticides in blindincurred samples.

Development of Analytical Method for Picoxystrobin in Agricultural Commodities Using GC/ECD and GC/MS

BACKGROUND: This study was conducted to develop analytical method for picoxystrobin in agricultural commodities using GC/ECD and GC/MS. METHODS AND RESULTS: Each steps of analytical method were optimized for determining picoxystrobin residues in various agricultural commodities. The developed methods include acetone extraction, n-hexane/saline water partition and florisil column chromatography for analysis of all samples (apple, potato, green pepper, hulled rice and soybean), and in addition to these steps, solid phase extraction (SPE) was used for analysis of green pepper and n-hexane/acetonitrile partition was used for analysis of hulled rice and soybean. The instrumental conditions were tested for quantitation in GC/ECD and for confirmation in GC/MS. Recovery was in the range of 86~109% with RSD 10.2% and the quantitation limits (LOQ) of method were 0.025 mg/kg in all agricultural commodities. CONCLUSION: The result showed that the developed method can be used to determine picoxystrobin residue in agricultural commodities.