An iron modified-magnetic nanoparticle (MNP) was used as solid-phase for extraction of diazinon residue in apples and compared with high performance liquid chromatography (HPLC). Fourier transform nanoparticles showed absorption peaks near 636cm, 3450corresponding to FeO and OH but coated particles peaked at 2929 aliphatic C-H, 3437 OH, 1726 C=O, 1601 OH, 1443 CH_2, 1036 CO and 1135 aliphatic SiO. Transmission electron imaging confirmed ~50nm particles. In acetonitrile required 20min for complete adsorption of 20ppm diazinon in 0.01 cibacron blue nano particles. Langmuir model (R~2= 0.9975) fitted best adsorption of diazinon by monolayer adsorption. For desorption, dichloromethane yielded 98.2%. Concerning 50ppm diazinon extraction from apple, we recovered 54% compared with 87% by HPLC. We find that 54-64% pesticide extraction with coated nanoparticles was insufficient for fruit but was 70% efficient for soil and water.
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