Determination of Mineral Elements Contents in Rosa roxburghii Tratt by Microwave Digestion and Flame Atomic Absorption Spectrometry

The microwave digestion conditions of Rosa roxburghii Tratt were optimized by orthogonal test,and then the contents of seven trace elements,including Fe,Mg,Mn,Zn,Cu,Pb and Cd in Rosa roxburghii Tratt were determined by flame atomic absorption spectrometry( FAAS). The results showed that the optimum conditions were as follows:the digestion agent was HNO3-H2SO4(4∶ 1),the solid-liquid ratio was 1∶ 20,the microwave power was 600 W,the digestion temperature was 140 ℃ and the hold time was4 min. The detection limits were 0. 003—0. 080 μg / m L,and the recoveries of the FAAS method were between 96. 25% —104. 20%,the relative standard deviations( RSD) were lower than 3. 04%. These figures showed that the FAAS method gave good accuracy and precision. The analytical results indicated that the contents of Fe,Mg,Zn were rich,the contents of Mn and Cu were medium,and the contents of Pb and Cd were low.