高效液相色谱-荧光检测器法同时测定蔬果中5种植物生长素残留  

Simultaneous Determination of 5 Phytohormone Residues in Vegetables and Fruits by High Performance Liquid Chromatography with Fluoresence Detector

作　　者：胡晓科[1] 邹海民[1] 薛勇 HU Xiaoke;ZOU Haimin;XUE Yong(Chengdu Center for Disease Control and Prevention , Chengdu 610041, China)

机构地区：[1]成都市疾病预防控制中心,成都610041

出　　处：《理化检验（化学分册）》2019年第3期309-313,共5页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：成都市科技局科技惠民技术研发项目(2015-HM01-00184-SF)

摘　　要：采用高效液相色谱-荧光检测器法同时测定蔬菜、水果中的吲哚-3-乙酸、吲哚-3-丙酸、吲哚-3-丁酸、2-萘氧乙酸、1-萘乙酸等5种植物生长素残留。取蔬菜或水果样品的可食部分,切碎并充分混匀,称取10.000g,加入20mL含0.2%(体积分数)甲酸的乙腈,高速匀浆2min,加入4g无水硫酸镁、1g氯化钠,涡旋5min后,以8 000r·min^(-1)转速离心5min,取10.0mL上清液蒸发至近干,用5mL含0.2%(体积分数)甲酸的二氯甲烷-乙腈(9+1)混合液复溶,溶液以1mL·min^(-1)流量通过氨基固相萃取小柱。收集流出液,在溶剂蒸发工作站上浓缩至近干,用甲醇溶解残渣并定容至1.0 mL,溶液经0.45μm滤膜过滤后,进行高效液相色谱分析。以Agilent Eclipse XDB-C18色谱柱(4.6mm×250mm,5μm)为固定相,用0.1%(体积分数)乙酸溶液与甲醇的混合液为流动相进行梯度洗脱;在激发波长287nm,发射波长337nm处进行荧光检测。结果表明:5种植物生长素的质量浓度均在0.050～5.0mg·L^(-1)内与对应的峰面积呈线性关系,检出限(3S/N)在0.93～2.0μg·kg^(-1)之间。对空白样品进行加标回收试验,回收率在72.4%～114%之间,测定值的相对标准偏差(n=6)低于4.6%。A method of high performance liquid chromatography with fluorescence detector was applied to the simultaneous determination of five phytohormones residues, including 3-indolyl-acetic acid, 3-indolepropionic acid, 3-indolebutyric acid, 2-naphthoxyacetic acid and 1-naphthylacetic acid, in vegetables and fruits. After the edible part of the vegetable or fruit sample was chopped and mixed well, 10.000 g was taken and added into 20 mL of acetonitrile containing 0.2%(volume fraction) formic acid. The mixture was homogenated for 2 min, then 4 g of anhydrous magnesium sulfate and 1 g of sodium chloride were added and the mixture was vortexed for 5 min. After centrifuging at 8 000 r·min^-1 for 5 min, 10.0 mL of the supernatant was taken and evaporated to near dryness. The residue was dissolved with 5 mL of dichloromethane-acetonitrile (9+1) mixture containing 0.2%(volume fraction) formic acid, and the solution was passed through an amino solid phase extraction cartridge at a flow rate of 1 mL·min-1. The effluent was collected, concentrated to near dryness on a solvent evaporation workstation, and the residue was dissolved with methanol and made up to 1.0 mL. The solution was filtered through a 0.45 μm filter membrane and analyzed by high performance liquid chromatography. An Agilent Eclipse XDB-C18 column (4.6 mm×250 mm, 5 μm) was used as stationary phase, and a mixture of 0.1%(volume fraction) acetic acid solution and methanol was used as mobile phase for gradient elution. Fluorescence detection was performed at the excitation wavelength of 287 nm and the emission wavelength of 337 nm. The results showed that, linear relationships were found between peak area and mass concentration of the 5 phytohormones in the same range of 0.050-5.0 mg·L-1, with detection limits (3S/N) in the range of 0.93-2.0 μg·kg-1. Tests for recovery was made by standard addition method on the base of blank samples, giving results in the range of 72.4%-114%, and relative standard deviations (n=6) less than 4.6%.

关 键 词：高效液相色谱法 荧光检测器 植物生长素 蔬菜 水果 

分 类 号：O657.7[理学—分析化学]