Determination of 27 elements in Maca nationality's medicine by microwave digestion ICP-MS / 中国中药杂志

An analysis method has been established to test 27 elements (Li, Be, B, Mg, Al, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Sr, Mo, Cd, Sn, Sb, Ba, La, Hg, Pb, Bi) in Maca nationality's medicine with microwave digestion-ICP-MS. Sample solutions were analyzed by ICP-MS after microwave digestion, and the contents of elements were calculated according to their calibration curves, and internal standard method was adopted to reduce matrix effect and other interference effects. The experimental results showed that the linear relations of all the elements were very good; the correlation coefficient (r) was 0.9994-1.0000 (Hg was 0.9982) ; the limits of detection were 0.003-2.662 microg x L(-1); the relative standard deviations for all elements of reproducibility were lower than 5% (except the individual elements); the recovery rate were 78.5%-123.7% with RSD lower than 5% ( except the individual elements). The analytical results of standard material showed acceptable agreement with the certified values. This method was applicable to determinate the contents of multi-elements in Maca which had a high sensitivity, good specificity and good repeatability, and provide basis for the quality control of Maca.

Investigation of elemental concentration and extraction rate of polysaccharides from Liuwei Dihuang prescription" by ICP-MS / 中国中药杂志

A method was established for the simultaneous analysis of 25 trace elements and heavy metals in polysccharides from Liuwei Dihuang prescription, including Li, Be, B, Ti, Mg, Al, V, Cr, Mn, Co, Fe, Ni, Cu, Zn, Ga, As, Sr, Cd, Sn, Sb, Ba, Hg, Tl, Pb, Bi. The different rate of elemental extraction in Al, Fe, Mg, B, Ti, Mn, Zn, Sr, Ba was made in water and different concentration of alcohol. The samples, digested via microwave, calibrated by internal standard elements such as Ge and In, with bush branches and leaves as the controlled reference standard, were inlet into ICP-MS to analyze the contents of the 24 trace elements and heavy metals. The detection limits of the 24 elements were in the range of 0.007-2.225 µg · L(-1), while the RSD was below ≤ 4. 0%, with their recovery ranging from 84. 1% to 116%. Big different of the elemental extraction rates could be found by using different ethanol solutions. The method is simple, rapid and accurate, and can be used for the quality control of trace elements and heavy metals in Liuwei Dihuang polysccharides. With the aid of the obtained result, we may increase the extraction of necessary element while making an attempt at multi-element speciation in polysccharides from Liuwei Dihuang.