Samples were first homogenized. The chopped sample was blended using a blender equipped
with a stainless steel cut unit, a glass jar of approximately 50 mL, and pulse options. Approximately 40
g of homogenized sample was placed into a 250 mL beaker. After spiking the solution with an
appropriate amount of methomyl, the contents of the beaker were allowed to stand at room temperature
for 10 minutes. The contents were mixed with a spatula to obtain a free-flowing powder. To this
solution, 2 mL acetonitrile (corresponding to 5% v/m of the electrolyte) was added, and the solution
was homogenized by shaking for 20 min to complete evaporation of the solvent. The sample was then
centrifuged at 3600 rpm for 15 min, and the liquid supernatant was analyzed by biosensor immersion
for the indicated incubation times.