食品中重金属元素痕量分析消解技术的 进展与应用

食品中重金属元素痕量分析消解技术是分析过程中最关键的步骤, 直接关系到分析方法的优劣。本文概述了干灰化、湿式消解、微波消解和高压罐消解4种方法的原理和特点; 根据重金属元素特性, 探讨了的各种消解方法的适用范围、应用情况、最新进展及其对不同元素和检测仪器的适用性。本文表明: 1. 控制消解过程的污染, 降低样品空白值是重金属痕量分析质量控制的关键点; 2. 高压罐消解法和微波消解法的样品空白值低于湿式消解法和干灰化法; 3. 应根据元素特性、检测目的以及样品空白值大小选择合适的前处理消解方法: 食品中汞的测定宜采用高压罐消解或微波消解法, 食品中砷的测定最好采用湿式消解法, 食品中铅、镉、铜、镍、铝和硼的质量控制考核或本底值测定可采用高压罐消解和微波消解, 而日常检测或半定量测定可采用湿式消解。

Progress and application in the digestion technology of trace heavy metal elements determination in food

The digestion technology in determination of trace heavy metal elements in food was the key step in the analysis process, which was directly related to the quality of the determination method. The principles and characteristics of dry ashing digestion, wet digestion, microwave digestion and high-pressure tank digestion methods were summarized in this paper. According to the characteristics of heavy metal element, applicable scope, application characteristics, the latest progress and applicability on detection instruments of various digestion methods were discussed. This conclusion was as follows: Controlling the pollution of digestion process and reducing the sample blank value were the key points of quality control of trace heavy metal elements determination; Sample blank values for high-pressure tank digestion and microwave digestion were lower than those for wet digestion and dry ashing digestion; According to the characteristics of elements, objective of detection and sample blank values, appropriate digestion methods were selected: Determination of mercury in food should adopt high pressure digestion or microwave digestion method; The determination of arsenic in food should adopt wet digestion; In addition, the assessment of the quality control for the determination of lead, cadmium, copper, nickel, aluminum and boron in food or the background value determination could adopt high pressure tank digestion and microwave digestion, and daily test or semi-quantitative determination could adopt wet digestion.