固相萃取-高效液相色谱法同时检测大米中12种磺酰脲类除草剂的残留

Simultaneous Determination of Twelve Sulfonyl Urea Herbicide Residues in Rice by High Performance Liquid Chromatography with Solid-Phase Extraction

建立了固相萃取前处理净化技术-高效液相色谱（HPLC）同时检测大米中12种磺酰脲类除草剂残留的方法。采用ENVI^TM-18（C18）硅胶柱和ENVI-Carb（GCB）石墨化碳柱对样品进行净化、萃取，采用C8柱，以乙腈和5mmol／L冰乙酸混合溶剂为流动相进行梯度洗脱，在240nm下进行检测。12种磺酰脲类除草剂在0．01～0．50μg／g添加范围内的回收率为72．2％～106．5%．相对标准偏差为0．6％～6.4％，检出限为0.01～0.02μg／g。

A high performance liquid chromatographic （ HPLC ） method with solid-phase extraction was developed for screening of 12 sulfonyl urea herbicides in rice. The sample was cleaned up and extracted with ENVI^TM-18 （C18） and ENVI-Carb （GCB） columns. The separation was performed on a Symmetryshield^TM RP8 column （4.6 mm i.d.×150 mm） with a linear gradient elution （acetonitrile and 5 mmol/L acetic acid as mobile phase）, and the wavelength of an ultraviolet detector was set to 240 nm for the detection. The linear range was 0.1 - 10 mg/L, and the correlation coefficients were 0.998 3 - 0.999 9. Recoveries from rice samples spiked with 12 suffonyl urea herbicides at spiking levels ranging from 0.01 - 0.50 μg/g were from 72.2% to 106.5%, with relative standard deviations from 0.6% to 6.4%. The lowest detection limits （S/N = 3） were 0.01 - 0.02 μg/g. The results indicate that the method is easier, faster, sensitive and has better purification effect. It also demonstrates that this multiresidue analytical method can meet the requirements for simultaneous determination of sulfonylurea herbicides in rice.