FAAS Determination of Copper,Iron and Zinc in Fruits with Non-complete Digestion

Samples of apricot,nectarine and strawberry were treated with mixed acid of HNO3-HClO4(3+1) at low heating temperatures by the non-complete digestion.Emulsifier TX-10 was added to the digested sample solution to dissolve the oil or fat separated out during the process of digestion.The reddish orange colored,transparent and homogenous solution obtained was used for FAAS determination for the contents of copper,iron and zinc.Condition of sample digestion as well as the interferences of the co-existing TX-10,mixed acid and impurities in the mixed acid were studied.Detection limits (3s/k) found for Cu,Fe and Zn were 0.019,0.145 and 0.009 mg·L-1 respectively.The proposed method was used in the determination of Cu,Fe and Zn in substantial fruit samples,the results obtained checked very well with those by the ashing method.