火焰原子吸收光谱法测定紫菜中铜的研究

Study on the determination of copper in the laver by flame atomic absorption spectrometry

建立了非完全消化-火焰原子吸收光谱法测定紫菜中铜的方法,样品在低温下用高氯酸:硝酸(V:V=1:3)混合酸消解,再用20%的OP乳化剂溶液溶解消解过程中产生的油脂,配制成均匀、透明的样品溶液。同时制备空白溶液。用标准曲线法测定,本法相对标准偏差为2.72%,回收率为98.7%～106.8%。方法检出限(3σ)为0.0015μg/mL。将该法与灰化法进行了比较,结果表明无显著性差异。

A method for determining of micro copper content in laver by incomplete digestion-flame atomic absorption spectrometry was studied.The laver sample was digested in a mixed acid consisting of HClO4-HNO3（V：V=1：3） at low temperature.The fat produced during the digestion process was dissolved by adding the emulsifier OP to make a homogeneous and transparent solution of the sample.The working curve method was applied,and a blank solution was used as reference.The detection limit（3σ） was 0.001 5 μg/mL.This method was used to determine the copper in laver,the relative standard deviation（RSD） was 2.72%,and the recoveries were 98.7%～106.8%.The analytical result obtained by the proposed method showed not significant difference compared with the traditional ashing method.