Single-step microwave digestion of food and biological samples for the quantitative conversion of Se into the +4 oxidation state

Recent achievements in chemical hydride generation inductively coupled and microwave induced plasmas with optical emission spectrometry detection

“…Commercially available spectrometers were applied for ICP-OES and the Ar plasma in these instruments was typically axially 1,5,7,8,16,17,20,21,24,26,30,[33][34][35]40,41,[43][44][45][46][47][48][49][50][51][52][53][54] viewed. Older apparatus with radial 2,6,9,[11][12][13][14]25,27,28,32,[36][37][38][39]42,[55][56][57][58][59][60][61][62] viewing of Ar-ICP were ...…”

“…Continuous flow (CF) HG was mostly carried out using commercially available HG systems compatible with spectrometers used for detection of hydride forming elements, i.e., Varian VGA-76P, 46 VGA-76, 5,50,52 and VGA-77, 41,43,49,51,60 Perkin-Elmer FIAS 400, 47 Thermo T-PHD, 54,65-67 GBC HG3000PII, 9 Jobin Yvon CMA, 6,56,57,62 Marathon MSIS 40 or Optolab Nova-2. 3,9 In these systems, reagents, i.e., acidified sample and alkaline THB solutions and in some cases an additional solution of HCl, 6,46,49,51,60 were delivered in separate streams to T-or Yjunctions where they instantly reacted after mixing.…”

“…Continuous flow (CF) HG was mostly carried out using commercially available HG systems compatible with spectrometers used for detection of hydride forming elements, i.e., Varian VGA-76P, 46 VGA-76, 5,50,52 and VGA-77, 41,43,49,51,60 Perkin-Elmer FIAS 400, 47 Thermo T-PHD, 54,65-67 GBC HG3000PII, 9 Jobin Yvon CMA, 6,56,57,62 Marathon MSIS 40 or Optolab Nova-2. 3,9 In these systems, reagents, i.e., acidified sample and alkaline THB solutions and in some cases an additional solution of HCl, 6,46,49,51,60 were delivered in separate streams to T-or Yjunctions where they instantly reacted after mixing. Resulting reaction mixtures were subsequently propelled to reaction coils 5,46,50,52 to finish the HG reaction or directly introduced to tubular gas-liquid phase separators (GLSs) where volatile hydrides and H 2 were released from the liquid phase while postreaction solutions were removed from systems by pumping them out to wastes.…”

Low volume microwave digestion and direct determination of selenium in biological samples by hydride generation-atomic fluorescence spectrometry

“…Unfortunately, there is little information in the literature. A recent paper [21] mentions that the introduction of NaCl into a HNO 3 -H 2 O 2 (5:1) digestion mixture allows a total mineralization of biological samples and any Se released would be in the form of Se (IV) after a MW digestion. The focus of this paper was however on the conventional MW digestion and differential pulse cathodic stripping voltammetry (DPCSV) measurement, rather than LVMWD and HG-AFS determination.…”

Determination of Se(iv) as a 5-nitropiazselenol complex by adsorptive stripping voltammetry at an in situ plated bismuth film electrode

“…Before analysis for elimination of organic compounds and other interfering agents, the samples were digested according to the method reported elsewhere. 52 Briey, an aliquot of 0.5 mL blood samples or 2.5 mL urine samples was added to 2.5 mL an oxidizing acid mixture containing nitric acid (65%, w/w), hydrogen peroxide (30%, w/w) in a volume ratio of 5 : 1 and 0.25 g mL À1 NaCl. Microwave digestion was carried out during three steps as follows: 2 min with an irradiation power of 250 W; 2 min with 0 W and 15 min with 300 W. Then the digested samples were cooled to room temperature and neutralized to pH ¼ 2.…”