噻苯隆及其异构体在棉籽和土壤中残留量测定方法

A Method for Determining Residues of Thidiazuron and its Isomers in Cotton Seeds and Soil

噻苯隆及其异构体在棉籽和土壤中残留量测定方法。棉籽样品用乙腈提取后,用正己烷萃取、分液,过碱性氧化铝层析柱;土壤样品用乙腈/去离子水提取,加饱和NaCl溶液,二氯甲烷萃取、分液,碱性氧化铝柱层析净化。高效液相色谱(二极管阵列检测器)法测定,250×4.6mmC18柱,流动相:乙腈∶水(55:45v/v);流速:1ml/min;波长:290nm;进样量:10μl。棉籽中TDZ回收率为80.4%￣95.4%,P-TDZ回收率为81.2%￣93.8%。土壤中TDZ回收率为82.0%￣95.4%,P-TDZ回收率为80.0%￣97.2%。相对标准偏差均低于7%。结果表明:色谱峰分离完全,回收率符合残留检测的要求,精密度高,线性范围宽,完全适用于测定噻苯隆及其异构体在棉籽和土壤中残留量的要求。

Residues of thidiazuron and its isomers were determined in cotton seeds and soil. Cotton seed samples were extracted with acetonitrile and partitioned with n-hexane, followed by clean-up on an alkaline aluminum oxide column. Soil samples were extracted with acetonitrile-deionized water, followed by addition of a saturated NaCl solution, partitioning with dichloromethane, and clean-up on an alkaline aluminum oxide column. Determination was conducted with HPLC using a diode array detector, a 250 × 4.6mm C18 column, and a mobile phase of acetonitrilc-water (55:45). Detection wavelength was 290 nm and flow rate of the mobile phase was l ml/min. Injection volume was 10 μl. The recovery ratios of TDZ and P-TDZ were 80.4-95.4% and 81.2-93.8%, respectively, in cotton seed, and were 82.0-95.4% and 80.0-97.2%, respectively, in soil. Relative standard deviation was <7%. The method resulted in chromatographic peaks that separated completely, recovery levels that were adequate for residue determination, high accuracy, and a wide range of linearity, indicating good suitability for determining residue levels of thidiazuron and its isomers in cotton seed and soil.