FAAS Determination of Microamounts of Iron Zinc Copper and Manganese in Cortex Albiziae with Microwave Irradiated Sample Digestion

Sample of cortex albiziae was digested with HNO3 and H2O2 by heating at 105-110 ℃ for 30 min and then in a microwave digestor at 650 W for 4 min.The transparent solution obtained was diluted to 100 mL in a volumetric flask and used for FAAS determination of microamounts of Fe3+,Zn2+,Mn2+ and Cu2+.Under the prescribed working condition of the instrument,detection limits (3S) of 0.013,0.003,0.008,0.003 mg·L-1 for Fe3+,Zn2+,Cu2+ and Mn2+ were found respectively.In analyzing a sample of cortex albiziae,values of RSD′s (n=10) found were 0.4% (for Fe),2.6% (for Zn),2.2% (for Cu) and 0.6% (for Mn).Values of recovery found were in the range of 98.0%-102.0%.