【作者】 季爱芳；

【导师】 王捍东；

【作者基本信息】 扬州大学 ， 临床兽医学， 2007， 硕士

【摘要】 随着工农业生产的快速发展,重金属污染已成为全世界日益关注的问题。20世纪的环境污染事件如日本的水俣病事件、痛痛病事件以及剧毒物污染莱茵河事件等,即因重金属污染引起。环境中的重金属可通过食物链最终进入人体,给人类健康造成严重危害。因此,动物性食品中砷、汞和硒的残留问题日益受到人们的关注,检测技术也成为当前研究的热点。原子荧光光谱法(AFS)是20世纪60年代发展起来的一种新型检测方法,灵敏度高、检出限低、干扰小,现已成为重金属As、Hg和Se检测应用最为广泛的仪器分析方法之一。但是目前仍没有双道检测汞-砷、砷-硒的国家标准发布。微波消解系统是一种先进的消解方式,以它的密闭高效、安全无污染等优势得到了广泛的应用。As、Hg和Se都是易挥发的元素,使用微波消解系统不易造成损失和污染、样品消解彻底,且环境污染小、工作时间短。本研究旨在利用微波消解系统、AFS-920原子荧光光度计,优化单元素检测条件,在此基础上探索双元素联测的方法,充分发挥仪器性能、进一步提高工作效率、降低分析成本。主要包括以下研究内容:应用AFS-920原子荧光光度计、微波消解前处理系统,研究了样品前处理条件(HNO3-H2O2)消解体系、预还原剂和KBH4-KOH的优化;仪器最佳检测条件的完善;抗干扰和增敏试剂的作用等对于检测As、Hg和Se检测的影响。通过试验记录和大量数据,建立联AFS联合检测汞-砷、砷-硒的检测方法。试验所确定的联测条件,能够满足两元素双道检测的要求,取得较好的灵敏度、精确度和准确度。在汞-砷联测的条件下,砷0μg/L～10μg/L工作曲线的相关系数为0.999,检测限为0.0238μg/L,相对标准偏差为1.91%;汞0～1.0μg/L工作曲线的相关系数为0.9992,检测限为0.0061μg/L,相对标准偏差为2.16%。在砷-硒联测的条件下,砷0μg/L～10μg/L工作曲线的相关系数为0.9992,检测限为0.0056μg/L,相对标准偏差为1.95%;硒0～10μg/L工作曲线的相关系数为0.9996,检出限为0.0326μg/L,相对标准偏差为3.26%。该方法可以不经过加入掩蔽剂、抗干扰剂、共沉淀分离和其它的分离富集手段,就能简便而准确的测定样品中的微量砷、硒和汞,具有很高的实用价值。更多还原

【Abstract】 Along with the development of industry and agriculture, heavy metal pollution has become a growing worldwide concern. The noxious substance was absorbed by anthropometric through food chain, which would lead to people’s intoxication. Now with the development of research, people think much more highly of heavy metals than ever before, and are paying much more attention to metal residue problems. How to detect and control metal contamination has become a popular question. Animal food is an important origin of metal in human body, so to find out a simple, quick, precise method to detect the metal content in chicken, pork, milk and eggs is very significant.Atomic fluorescence spectrometry is an analytical technique, which was developed in 1960s’. The technique has many virtues, such as simple spectral line, high sensitivi- ty, low detection limit and multi-element analysis. We use it to detect arsenic, seleni- um and mercury. But there is no national standards issued for dual-channel detection of arsenic and mercury, arsenic and Se, mercury and Se.Microwave oven which heats samples by the principle of molecular collision and controlls pressure by indutor, is safe, efficient, and has no pollution, so it is very popular to analysts. Arsenic selenium and mercury can be lost easily with the utilization of uncovered digestion, for their high evaporability.This study was to optimize the conditions for single-element detection, and on the basis of it, we searched for the conditions of double-element measurementm, in order to improve work efficiency and lower the analysis cost. We did the following work by using AFS-920 and microwave digestion systems. To perfect the detection conditions and increase detection sensitivity, we performed experiments to choosed the best pre-treatment methods, reductant concentration, instrument performance parameter, and counter-interference reagent.Through analyzing a large amount of data and test records, we explored the best conditions of double-element detection. The proposed method was provided with linear response ranges from 0 to 10μg/L for As and 0 to 1.0μg/L for Hg, and the detection limits of 0.0236μg/L and 0.0061μg/L were obtained for As and Hg respectively. The precision is 1.91% and 2.16% (R.S.D., n = 11). The proposed method was provided with linear response ranges from 0 to 10μg/L for As and 0 to 10μg/L for Se, and the detection limits of 0.0056μg/L and 0.0326μg/L were obtained for As and Se respectively. The precision is 1.95% and 3.26% (R.S.D., n = 11).The established dual-channel detection met- hod of two elements achieved better sensitivity, precision and accuracy, without mask- ing agent, separation. And this method was valuable in practical analysis.更多还原