光谱学与光谱分析, 2017, 37 (11): 3606, 网络出版: 2018-01-04
分散液液微萃取-原子荧光光度法测定大米中的汞
Determination of Mercury in Rice with Dispersive Liquid-Liquid Microextraction and Atomic Fluorescence Spectrometry
大米 原子荧光光谱法 分散液液微萃取 双硫腙 汞 Rice Atomic fluorescence spectrometry Liquid-liquid microextraction Dithizone Mercury
摘要
硝酸-高氯酸(4∶1, V/V)混合酸消解样品。 双硫腙为络合剂, 乙醇为分散剂, 四氯化碳为萃取剂, 建立了分散液液微萃取-原子荧光光度法测定大米中的汞的方法。 优化了原子荧光光度计工作参数和分散液液微萃取的最佳络合酸度、 络合剂用量、 萃取剂种类及用量等条件。 实验表明, 在最佳条件下, 方法的线性范围为0.005~25 μg·L-1, 相关系数为0.996 6, 检出限为0.003 μg·L-1, 相对标准偏差为3.84%, 加标回收率为90%~120%。 该方法灵敏度高, 分析速度快, 准确性高, 能有效检测大米中的痕量汞。
Abstract
Rice samples were digested by a mixture of nitric and perchloric acids (4∶1, V/V). Dithizone was used to chelate mercury ion in the sample solution, and the mercury complex was dispersed in ethanol before being extracted into carbon tetrachloride. Thus, a method of determining mercury in rice by dispersion liquid micro extraction-atomic fluorescence spectrometry was established. The operating parameters of the instrument and optimal experimental conditions of dispersive liquid-liquid microextraction were optimized, including the best complex acidity, the amount of complexing agent, extraction solvent type, the amount of dispersant dosage, and the extraction time. Experiments showed that under optimal conditions, the linear range was 0.005~25 μg·L-1 and the correlation coefficient was 0.996 6 with the detection limit of 0.003 μg·L-1, the relative standard deviation (RSD) of 3.84%, and the recovery 95%~105% . The method is proven to be a sensitive, rapid, and accurate,way which can detect effectively trace amounts of mercury in rice.
陆建平, 覃梦琳, 布静龙, 邓扬辉, 童张法. 分散液液微萃取-原子荧光光度法测定大米中的汞[J]. 光谱学与光谱分析, 2017, 37(11): 3606. LU Jian-ping, QIN Meng-lin, BU Jing-long, DENG Yang-hui, TONG Zhang-fa. Determination of Mercury in Rice with Dispersive Liquid-Liquid Microextraction and Atomic Fluorescence Spectrometry[J]. Spectroscopy and Spectral Analysis, 2017, 37(11): 3606.