摘要
目的寻找最优基体改进剂用于石墨炉原子吸收光谱法(graphite furnace atomic absorption spectrometry,GFAAS)测定水产干制品中痕量镉。方法采用微波消解,塞曼效应扣除背景干扰,分别以不同浓度硝酸铵、磷酸二氢铵、钯、氧化镧和EDTA为基体改进剂,标准曲线法测定水产干制品中镉含量。结果硝酸铵作基体改进剂,可最有效地消除该类食品中的基体干扰,且灵敏度较高。测定的最佳条件为:硝酸铵浓度5 g/L,灰化温度700℃,原子化温度1500℃,测定波长228.8 nm。在0~6μg/L浓度范围内,镉浓度与其吸光度呈良好线性关系,相关系数为0.9995,检出限为2μg/kg,加标回收率在93%~102%之间,相对标准偏差(relative standard deviation,RSD)为2.38%。结论在水产干制品中含盐量较高的情况下,以5 g/L硝酸铵为基体改进剂可较为有效地消除GFAAS测镉的基体干扰,从而使分析结果更加准确可靠。
Objective To obtain optimal matrix modifier for the determination of trace cadmium in dried aquatic products by graphite furnace atomic absorption spectrometry（GFAAS）. Methods Microwave digestion was adopted, and the background interferences were deducted by Zeeman effect, and the cadmium content in dried aquatic products was measured by standard curve method with different matrix modifiers, which included various concentrations of ammonium nitrate, ammonium dihydrogen phosphate, palladium, lanthanum oxide and EDTA. Results Ammonium nitrate as matrix improver could effectively eliminate the interference of the matrix in this kind of food, and the sensitivity was high. The optimal conditions were found as follows： ammonium nitrate concentration was 5 g/L, ashing temperature was 700 ℃, the atomization temperature was 1500 ℃, and measure wavelength was 228.8 nm. In the concentration range of 0-6 μg/L, the cadmium concentration was in good linear relation with its absorbance, and the correlation coefficient was 0.9995. The limit of detection was 2 μg/kg, and the recoveries were 93%-102% with the relative standard deviation（RSD） of 2.38%. Conclusion In the case of high salt content in dried aquatic products, it is more effective to eliminate the matrix interference of GFAAS by using 5 g/L ammonium nitrate as matrix improver, so as to make the analysis result more accurate and reliable.
作者
辜世伟
黄先亮
刘顶
何春兰
艾馨
GU Shi-Wei;HUANG Xian-Liang;LIU Ding;HE Chun-Lan;AI Xin(Chongqing Institute for Food and Drug Control, Chongqing 401121, China;Food Safety Inspection Technical Demonstration Center for Food Industry, Chongqing 401121, China)
出处
《食品安全质量检测学报》
CAS
2018年第10期2379-2383,共5页
Journal of Food Safety and Quality
关键词
基体改进剂
石墨炉原子吸收光谱法
水产干制品
镉
matrix modifier
graphite furnace atomic absorption spectrometry
dried aquatic products
cadmium
