A rapid method for the determination of trace Cu and Fe in edible salad oil by graphite furnace atomic absorption spectroscopy

In the determination of trace amounts of copper and iron in edible salad oils by graphite furnace atomic absorption spectroscopy (GFAAS), an ashing method with low temperature oxygen plasma was used to effectively eliminate the interference of the organic matrix. Two sample preparation methods were studied, extraction with concentrated nitric acid followed by ashing with the low temperature oxygen plasma to determine the yield of extraction, and direct analysis of the metal content after dilution with methyl isobutyl ketone (MIBK). Results obtained from these methods were compared with the background absorbance by inductively coupled plasma‐atomic emission spectroscopy (ICP‐AES).