Continuous FAAS determination of copper, zinc, iron, and manganese in pineapple

A method of digesting pineapple sample in microwave digestion jar and detecting copper, zinc, iron and manganese in the same digested solution with FAAS was discussed. The influence of the amount of nitric acid and hydrogen peroxide for digestion, and the digestion time on the result was studied. Interference among copper, zinc, iron and manganese in the same solution was investigated. Under the optimized conditions, the detection limits of the method were 0.0060 μg/mL for copper, 0.0074 μg/mL for zinc 0.0040 μg/mL for iron, and 0.009 μg/mL for manganese. The relative standard deviations of the method were between 1.9%～4.7%,and the recoveries were in the range 93.2%～105%.μg