MPT-AES法测定核桃油中铜和铁

Determination of Copper and Iron in Walnut Oil by MPT-AES

用微波等离子炬(MPT)作激发光源,氩气为载气,用气动雾化进样,研究了微波等离子体炬原子发射光谱法(MPT-AES)测定核桃油中铜和铁元素。考察并优化了微波功率、工作气流量、载气流量、氧屏蔽气流量、酸效应、共存离子等实验参数。测定铜和铁的检出线分别为5.3,22.1 ng/mL。RSD均小于3.2%,线性范围分别为0.05-100,0.1-100μg/mL,加标回收率均在96.4%-102.2%。

The analytical methods for copper and iron element in walnut oil were studied by microwave plasma torch atomic emission spectrometry （MPT-AES） using microwave plasma torch （MPT） as excitation light source, argon as supporting gas, and peneumatic nebulization sampling system. Some experimental parameters （including microwave power, carrier gas flow rate, supporting gas flow rate, oxygen shied gas flow rate, effect of acid, coexistence ions） were investigated and optimized. The linear ranges of copper and iron is 0.05 - 100,0.1- 100 μg/mL, respectively. The detection limits is 5.3,22.1 ng/mL, respectively. The recoveries are both in the range of 96.4 % - 102.2 % and the RSD of the method is less than 3.2 %.