Metal speciation by supercritical fluid extraction with on-line detection by atomic absorption spectrometry.

摘要: A silica flame-in-tube interface is described for the sensitive detection, by AAS, of As, Cd, Cu, Mn, Pb, Se, or Zn in supercritical (SC) fluid extractor eluate. In operation, analyte metal aqueous medium derivatized situ complexation with tetrabutylammonium dibutyldithiocarbamate (TBADB-DTC) and product complex mobilized into SC-CO2. The extraction process equally efficient whether mobile phase presaturated complexing agent during a static preequilibration stage this reagent solubilized dynamically as traverses saturation vessel placed series vessel. SC-CO2 eluate nebulized diffused flame maintained within upper region tube optical interface. Optimal conditions separate flows O2 H2 to base are slightly reducing phases but oxidizing methanolic phase. For each element, limits detection were subnanogram low picogram if standard was flow injected These sensitivities permitted differences rates mobilization from different matrices be explored technique probing interactions matrix. portion total burden fresh bovine liver slurry rapidly absence agent, remainder more than freeze-dried reference material tissue.