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目的建立顶空-固相微萃取-气相色谱法测定甘蔗中莠去津残留量的方法。方法称取混匀样品于10 ml顶空瓶中,加入乙酸盐缓冲液及氯化钠溶液,50℃搅拌预热2 min,用聚二甲基硅氧烷萃取头(PDMS,100μm)在500 r/min搅拌下顶空萃取20 min,在280℃进样口解吸3.0 min,用HP-INNOWAX毛细管色谱柱分离,ECD检测器检测甘蔗中莠去津的残留量。结果莠去津的浓度为0.005μg/g~0.20μg/g时,线性关系良好,相关系数(r)=0.999 6,方法的检出限为0.000 06 mg/kg,平均回收率为95.8%~98.6%,相对标准偏差(RSD)为2.3%~4.9%。结论顶空-固相微萃取-气相色谱法测定甘蔗中莠去津残留量的方法,无需有机溶剂,集萃取分离、浓缩净化、解吸、进样等过程于一体,具有环保、操作简便、快速、基质干扰少、灵敏度高、测定范围宽,分析结果准确可靠,适用于甘蔗样品中莠去津残留量的测定。
Objective To establish a method for the determination of atrazine residues in sugarcane by headspace-solid phase microextraction-gas chromatography. Methods Weigh the sample mix in 10 ml headspace bottle, add acetate buffer solution and sodium chloride solution, preheat at 50 ℃ with stirring for 2 min, use polydimethylsiloxane extraction head (PDMS, 100μm) The headspace extraction was performed at 500 r / min for 20 min and desorbed at 280 ℃ for 3.0 min. The residue was separated on a HP-INNOWAX capillary column. The residue of atrazine in sugarcane was detected by ECD detector. Results Atrazine concentration of 0.005μg / g ~ 0.20μg / g, the linear relationship was good, the correlation coefficient (r) = 0.999 6, the detection limit of the method 0.000 06 mg / kg, the average recovery was 95.8% 98.6%, and the relative standard deviation (RSD) was 2.3% ~ 4.9%. Conclusion The method of headspace-solid-phase microextraction-gas chromatography for the determination of atrazine residues in sugarcane without organic solvents, extraction and separation, concentration purification, desorption, injection and other processes in one, environmentally friendly, easy to operate, fast , Less matrix interference, high sensitivity, wide measuring range, accurate and reliable analysis results, and is suitable for the determination of atrazine residues in sugar cane samples.