摘要
考察吡虫啉在番茄中的残留消解动态,改进吡虫啉在番茄中的残留分析方法,并对日常生活中几种常用的去除农药残留的方法进行比较。结果表明:采用乙腈提取、氨基固相萃取小柱净化、高效液相色谱分离测定番茄中的吡虫啉残留,方法在0.01～2mg/L的范围内,吡虫啉的峰面积与其质量浓度呈良好的线性关系,线性方程为Y=69582.5X+68.9,相关系数为0.9999。向空白番茄中添加吡虫啉标样,使其添加量为0.01、0.02、0.1mg/kg和1.0mg/kg时,平均回收率在87.5%～96.5%之间,相对标准偏差低于6.7%,番茄中吡虫啉残留的最小检测限量为0.01mg/kg。该方法简便、快速、准确。吡虫啉在番茄中的残留量随时间的延长而逐渐降低,消解动态曲线符合一级动力学方程:C=0.1159e-0.1991t,半衰期为3.48d。采用家庭常用的清水、热水、洗洁精等浸泡冲洗番茄的方法,可以在一定程度上去除番茄中吡虫啉残留,但热水和洗洁精清洗的方法并不优于清水清洗。
The residual dynamics of imidacloprid in tomatoes was investigated and the best solid-phase extraction column was selected for the HPLC-MS analysis of imidacloprid. Meanwhile,a comparative study of commonly used methods for removing residual imidacloprid from tomatoes was performed. A HPLC-MS analytical method based on extraction with acetonitrile and clean-up on a NH2 solid-phase extraction column was developed for the determination of imidacloprid residue in tomatoes. There was a good linear relationship between the peak area and concentration of imidacloprid over the range from 0.01 to 2 mg/L,and the linear equation was Y = 69582.5 X ＋ 68.9,with a correlation coefficient of 0.9999. The mean recoveries of the method varied from 87.5% to 96.5% with a relative standard deviation ranging from 1.7% to 6.7% at four fortification levels in the range from 0.01 to1.0 mg/kg,and the limit of detection was 0.01 mg/kg. This method is characteristic of simplicity,rapidity and accuracy. The degradation dynamics suggested that imidacloprid degraded gradually with prolonged time,that the degradation dynamic curve complied with first-order kinetics equation,and that the half-life of imidacloprid in tomatoes was 3.48 day. Rinsing with tap water,hot water or detergent was employed to remove imidacloprid residue. The results revealed imidacloprid residue reduction could be attained to a certain extent,whereas the effectiveness of rinsing with hot water and detergents was not superior to that of rinsing with tap water.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2010年第19期133-136,共4页
Food Science
基金
湖北省农业科技创新中心项目(2010-620-001-03)
关键词
吡虫啉
番茄
高效液相色谱法
残留消解动态
去除农药残留
imidacloprid
tomato
high-performance liquid chromatography
residual dynamics
removal of pesticide residues
