Page 4 of 797 VA Computrace by Metrohm AG

application 1 ­ voltammetric trace analysis analysis of heavy metals ­ total concentration for a fraction of the purchase price of an aas or icp instrument it is possible to carry out metal analyses with the same or improved sensitivity the only thing required apart from small amounts of reagents is a small amount of pure nitrogen no expensive flammable gases no specially constructed fume hoods in the laboratory no costly metal vapor lamps and speciation spectroscopic methods can only determine the total concentration of the metals with voltammetry it is additionally possible to differentiate between various oxidation states of metal ions or between free and bound metal ions this allows statements to be made about the biological availability and toxicity of heavy metals and makes this technique an essential element in environmental analysis with spectroscopy it is only possible to make comparable statements after the complicated separation of the metal species high ionic concentrations no problem with va samples with high ionic concentrations are not a problem for voltammetry this means that voltammetry is predestined for the analysis of · water wastewater and seawater · salts pure chemicals · electroplating baths · foodstuffs detection limits antimony sbiii/sbv arsenic asiii/asv bismuth bi cadmium cd chromium criii/crvi cobalt co copper cu iron feii/feiii lead pb mercury hg molybdenum moiv/movi nickel ni platinum pt rhodium rh selenium seiv/sevi thallium tl tungsten w uranium u zinc zn 1 ppt 1 ng/kg 200 100 500 50 25 50 50 50 50 100 50 50 0.1 0.1 300 50 200 25 50 ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt ppt 4

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