抑霉唑硫酸盐在柑橘果实中的降解规律研究

Study on degradation of imazalil sulfate in citrus

【目的】为柑橘抑霉唑硫酸盐的合理使用提供科学依据,【方法】采用浸果法对抑霉唑硫酸盐在柑橘中消解动态进行了研究。样品中的抑霉唑硫酸盐用甲醇提取,液液分配去除杂质,离子对高效液相色谱检测。【结果】当添加水平为0.10～5.0 mg.kg-1时,添加回收率为73%～91%,相对标准偏差为1.5%～5.8%,最低检测浓度为0.10 mg.kg-1。抑霉唑硫酸盐在柑橘全果和橘皮中的降解动态曲线符合一级动力学方程,半衰期分别为63 d和60 d。【结论】该检测方法的灵敏度、精确度、准确度均满足农药残留检测要求。抑霉唑硫酸盐在柑橘上降解较快。

[Objective]The study was to provide a scientific basis for reasonable use of imazalil sulfate in citrus. [Method]The residue decline of imazalil sulfate in citrus was investigated by dipping the fruits. The imazalil sulfate residue was extracted with methanol. The extract was cleaned up through liquid-liquid extraction. Then, imazalil sulfate was analyzed by ion-paired reversed high performance liquid chromatography. [Result]This method was validated at 0.10, 1.0, and 5.0 mg kg^（-1） imazalil sulfate concentrations. These recoveries were from 73% to 91%, with the coefficient of variation within 5.8%. The limit of quan- tification was 0.10 mg· kg^（-1） imazalil sulfate. The dissipation of imazalil sulfate residues with time was in accordance with the first-order kinetics equation. The half-leaf in citrus fruit and citrus peel were 63 d and 60 d, respectively. [Conclusion]The sensitivity, accuracy and precision of this method meet the requirement of imazalil sulfate residue analysis. Imazalil sulfate belongs to the easily degradable in citrus.