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Pyrethroid pesticides and organochlorine pesticides are two classes of pesticides that are generally used for the control of a broad range of pests on fruits, vegetables, and grain crops. The analysis methods of pyrethroid and organochlorine pesticides residues in foods and environmental samples have received considerable attention in recent years.Electrospun polymer nanofiber is a new solid material that gained importance due to its special properties. Of its high porosity and large specific surface area, it has great chemical activity and a very high adsorption capacity. The preconcentration and separation of weak polar substances using a solid-phase extraction column packed with electrospun polymer nanofiber, should be a certain degree of practical significance.Two parts is given in the thesis:1. The determination of pyrethroid pesticides residues in vegetable with electrospun polymer nanofiber packed solid-phase extraction column by HPLCWe research the basic properties of PS electrospun polymer nanofiber as solid-phase extraction adsorbent. A solid-phase extraction column packed with electrospun polymer nanofiber was used to determinate six pyrethroid pesticides (fenpropathrin, λ-cyhalothrin,5-methrin, fenvalerate, permethrin and bifenthrin) in vegetable sample by HPLC. The exchange behaviours of PS electrospun polymer nanofiber for six pyrethroid pesticides were systematically explored. The influences of organic solvent and elution conditions on absorption of electrospun polymer nanofiber for six pyrethroid pesticides were also studied.The nanofiber had maximum adsorption capacities for fenpropathrin, Xλ-cyhalothrin,5-methrin, fenvalerate, permethrin and bifenthrin,5.4,5.8,6.0,6.5,6.5and8.0μg/mg, respectively. Under the optimum experimental conditions, six pyrethroid pesticides were separated from each other, and there was the linear relationship between the pesticides in the concentration ranges of (0.01～0.04)～10mg/L and the peak areas (r2=0.9995-0.9999). The limits of detection ranged from5to12μg/L, and the spiked recoveries of cabbage sample ranged between85.8%-96.6%with RSDs of2.7%-5.8%. 2. The determination of organochlorine pesticides residues in soil with electrospun polymer nanofiber packed solid-phase extraction column by GCA solid-phase extraction column packed with PS electrospun polymer nanofiber was used to determinate seven organochlorine pesticides (PDCB, α-BHC, γ-BHC, HCB, PCNB, p, p’-DDE and p, p’-DDT) in soil sample by GC-ECD. The exchange behaviours of PS electrospun polymer nanofiber for even organochlorine pesticides were systematically explored. The influences of organic solvent, pH, absorption and elution conditions on the absorption of electrospun polymer nanofiber were also studied.The nanofiber had excellent adsorption properties for PDCB, α-BHC, γ-BHC, HCB, PCNB, p, p’-DDE and p, p’-DDT, and the maximum adsorption capacities were8.3,8.0,8.5,7.7,6.5,7.6and7.5μg/mg, respectively. Under the optimum experimental conditions, seven organochlorine pesticides were separated from each other, and there was the linear relationship between the pesticides in the concentration ranges of0.8～ 103μg/L and the peak areas (r2=0.9988～0.9997). The limits of detection ranged from0.5to7.0μg/L, and the recoveries of spiked cabbage sample ranged between72.5%～93.6%with RSDs of2.7%～6.8%.
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