微波消解-石墨炉原子吸收法测大米粉中镉含量的方法研究

Determination of Cadmium Content in Rice Flour by Microwave Digestion-Graphite Furnace Atomic Absorption Spectrometry

目的:工业废水、废气的排放,以及含镉化肥的使用,导致海鲜水产品、粮食作物、蔬菜等不同程度的受镉污染,因此迫切需要优化镉含量的检测方法,准确检测镉元素的含量。在标准GB 5009.15—2014的指导下,以石墨炉原子吸收法测大米粉中镉含量为例,对试样的制备、消解,标液的配制、仪器条件的设定、标准曲浓度梯度配制等每一个环节进行优化,以提高墨炉原子吸收法测大米粉中镉含量的准确性。方法:通过测定已知镉含量的大米粉标准样品中的镉含量,不断优化实验条件,使实验测定值无限接近真实值,确定出微波消解-石墨炉原子吸收法测大米粉中镉含量的最优方法,并将此方法应用于试样含量的测定。结果:测量范围、相对标准偏差、方法检出限和标准曲线线性相关系数等符合要求。

Objective:The discharge of industrial waste water and waste gas,and the use of cadmium-containing chemical fertilizer,lead to different degrees of cadmium pollution in seafood,food crops,and vegetables.Therefore,it is urgent to optimize the detection method of cadmium content,and accurately detect the content of cadmium elements.Under the guidance of standard GB 5009.15—2014,taking the content of cadmium in rice noodles by graphite furnace atomic absorption method as an example,sample preparation,digestion,standard configuration,instrument condition setting and standard curvature concentration gradient preparation were optimized,so as to improve the accuracy of cadmium content in rice noodles by atomic absorption method of ink furnace.Methods:By determining the cadmium content in the standard samples of rice noodles with known cadmium content,constantly optimizing the experimental conditions to the real value,the optimal method of microwave digestion-graphite furnace atomic absorption method was applied to the determination of sample content.Results:Measurement range,relative standard deviation,method detection limit and linear correlation coefficient of standard curve meet the requirements.