In this research, combination of microextraction in packed syringe (MEPS) and positive mode corona discharge ionization ion mobility spectrometry (CD-IMS) was used for preconcentration and determination of diazinon in agricultural wastewater, underground and river water. MEPS is a technique for miniaturized SPE, promising comparable results relative to conventional SPE technique. MEPS was performed by using 2.0 mg of solid phase material (nanoclay/sol–gel( inserted into a gas-tight syringe (250 ?L). In this project, the synthesis of sorbent was done in nanoclay bed base on sol-gel technology. Because of the layered structure of nanoclay, using these particles increases porosity of sorbent. The sorbent was conditioned first with methanol and then with purified water (2×200 ?L each solvent). The water sample was drawn through the syringe and discard in waste (extract–discard) with speed of 2.5 ?L/s and this step was repeated for 10 times (200 ?L in each cycle). It was performed by a variable speed stirring motor which was attached to a circular plate. After removing interferences by 200 µL purified water, the sorbent was dried by a gentle stream of nitrogen gas during 10 minutes. Then, the analytes were eluted with 30 ?L methanol at speed of 1.0 ?L/s and the eluent was injected to CD-IMS injector. The cleaning of the solid phase was performed using 7×200 ?L methanol then 7×200 ?L purified water. The detection limit was 0.07 ?g/L, and the relative standard deviations were 5 to 12%. The applicability of the proposed methods was demonstrated by analyzing spiked real water samples. The relative recoveries obtained in the range of 95 to 106%. The obtained results revealed the capability of the proposed method for diazinon analysis in various real samples.
