Analysis of stobilurins in wheat grains using DART-TOFMS
Strobilurins, systemic pesticides originated from natural fungicidal derivatives, play an important role in control of various plant pathogens. Because of their unique protective properties, significant yield enhancements and longer retention of green leaf tissue, strobilurins have been widely used in agriculture since their introduction on the market in 1992. As other pesticides, these compounds are involved in control and monitoring surveys undertaken by regulation authorities.
The AccuTOF-DART system equipped with an AutoDart HTC PAL autosampler was used for the analysis of strobilurin residues (listed in Table 1) in wheat grain extracts. Crude extracts were prepared by shaking 12.5 g of sample with 50 mL of ethyl acetate and 5 mL of Na2SO4, the suspension was then filtered and the volume was made up to 25 mL by rota vapour. Within the validation, extracts spiked with strobilurins in the range from 12 to 1200 ng/g were analyzed. For quantitative analysis, prochloraz was used as an internal standard (samples were spiked with this internal standard at a level of 250 ng/g).