高效液相色谱—串联质谱法测定武夷岩茶中草甘膦残留的研究与分析

发布时间：2018-11-13 08:06

【摘要】：草甘膦,是一种非选择性内吸传导型广谱除草剂,能有效对禾本科阔叶杂草进行防除,是迄今世界上应用最广、生产量最大的除草剂。草甘膦作为一种毒理性较强的农药,它主要以富集的方式危害人畜或生态环境。随着茶产业的不断发展壮大,茶园面积迅猛扩张,劳动成本成倍增加,导致部分茶园使用草甘膦作为除草剂,从而使草甘膦在茶叶中残留。国内外对食品中的草甘膦残留已有较为成熟的检测方法,然而对武夷岩茶中的草甘膦残留量的检测却未见文献报道。本研究采用高效液相色谱-串联质谱技术建立了武夷岩茶样品中草甘膦残留量的测定方法。样品经二氯甲烷+水(1：1)提取和阳离子交换(Bio-Rad CAX)净化后,在硼酸盐缓冲液中与1.0mg/mL9-芴甲酯-氯甲酸(FOMC-Cl)丙酮溶液进行衍生化反应,以1%乙酸铵溶液和乙腈为流动相,质谱检测采用电喷雾正离子化模式和多反应监测模式。结果表明,草甘膦在1 ng/mL—10 ng/mL浓度范围内线性关系良好,线性相关系数R2=0.998。通过对空白武夷岩茶样品进行3个浓度水平的加标回收实验(n=6),草甘膦的平均回收率在78.6%-94.6%之间,相对标准偏差(RSD)为5.92%-7.559%。同时,为了更全面地了解和掌握不同山场、不同品种的武夷岩茶中草甘膦的残留情况,本文研究比较了10个正岩山场,10个半岩山场以及3个洲茶山场中水仙、肉桂、白鸡冠、铁罗汉、北斗、雀舌、半天妖、金锁匙、水金龟、白瑞香等10个武夷岩茶品种中草甘膦农药的残留情况。实验结果显示,正岩山场的各种武夷岩茶均未检出草甘膦残留,半岩山场部分检出微量草甘膦残留,洲茶山场中检出少量草甘膦残留。由此说明目前武夷岩茶中草甘膦的使用量少,残留水平低。
[Abstract]:Glyphosate (glyphosate) is a kind of broad-spectrum herbicide with non-selective internal absorption and conduction, which can effectively control the grass broad-leaved weeds. So far, it is the most widely used herbicide in the world and the largest amount of herbicides. Glyphosate (glyphosate) is a kind of pesticide with strong toxicology. It mainly harms people and animals or ecological environment by means of enrichment. With the development of tea industry, the area of tea garden expands rapidly and the labor cost increases exponentially. As a result, glyphosate is used as herbicide in some tea gardens, so that glyphosate residues in tea leaves. There are mature methods for the determination of glyphosate residues in food at home and abroad, but the determination of glyphosate residues in Wuyi rock tea has not been reported in literature. A high performance liquid chromatography-tandem mass spectrometry (HPLC / MS) method was developed for the determination of glyphosate residues in the samples of Wuyi rock tea. The samples were extracted from dichloromethane water (1:1) and purified by cation exchange (Bio-Rad CAX), and then reacted with 1.0 mg / mL ~ (9) fluorenyl-methyl chloroformate (FOMC-Cl) acetone solution in borate buffer solution. With 1% ammonium acetate solution and acetonitrile as mobile phase, electrospray ionization mode and multi-reaction monitoring mode were used for mass spectrometry. The results showed that glyphosate had a good linear relationship in the concentration range of 1 ng/mL-10 ng/mL, and the linear correlation coefficient R _ 2 ~ (2 +) was 0.998. The average recovery rate of glyphosate was between 78.6% and 94.6%, and the relative standard deviation (RSD) was 5.92-7.559%. At the same time, in order to understand and master the residue of glyphosate in different mountain fields and different varieties of Wuyi rock tea, this paper studied and compared 10 normal rock fields, 10 semi-rock mountain farms and 3 Zhou tea farms, including narcissus, cinnamon and white chicken crowns. Iron Luo Han, Beidou, Finch tongue, Half-day Monster, Gold key, Water Tortoise, White Naphtha and other 10 varieties of Wuyi Rock Tea residues of glyphosate pesticide. The results showed that glyphosate residue was not detected in all kinds of Wuyi rock tea in Zhengyan mountain field, trace glyphosate residue was detected in half rock mountain field, and a small amount of glyphosate residue was detected in Zhou tea farm. This shows that the use of glyphosate in Wuyi rock tea is low and the residual level is low.
【学位授予单位】：福建农林大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O657.63;TS272.7

【相似文献】