Nickel determination ETAAS

Analytical Methods and Speclatlon Electrothermal atomic absorption spectrophotometry (ETAAS), differential pulse adsorption voltammetry (DPAV), isotope-dilution mass spectrometry (ID-MS), and inductively coupled plasma mass spectrometry (ICP-MS) furnish the requisite sensitivity for measurements of nickel concentrations in biological, technical and environmental samples (Aggarwal et al. 1989, Case et al. 2001, Stoeppler and Ostapczuk 1992, Templeton 1994, Todorovska et al. 2002, Vaughan and Templeton 1990, Welz and Sperling 1999). The detection limits for nickel determinations by ETAAS analysis with Zeeman background correction are approximately 0.45 jg for urine,... 

Table 8.22 presents the results of the comparison of different methods used in this certification. The CVs within one method are generally of the same order of magnitude as the CVs between different techniques. For ICPMS (cadmium), ETAAS (nickel) and FAAS (zinc) the larger CVs are due to operating close to the limits of determination ... 

J.-H. Wang, E.H. Hansen, Coupling on-line preconcentration by ion-exchange with ETAAS. A novel flow injection approach based on the use of a renewable microcolumn as demonstrated for the determination of nickel in environmental and biological samples, Anal. Chim. Acta 424 (2000) 223. 

The Ni contents of the four fractions are determined by ETAAS. Vincent et al. (2001) used a similar approach based on differential step-wise leaching of nickel from aerosol particles that had been fractionated with a cascade impactor. For fractionation of nickel species in natural waters, Mandal et al. (2002) used Chelex-100 as a competing ligand to measure the rate of Nk released by dissociation of nickel in dissolved organic carbon complexes. 

Todoeovska N, Kaeadjova 1 and StafilovT (2002) ETAAS determination of nickel in serum and urine. Anal Bioanal Chem 373 310-313. 

Fang and Dong [3] determined nickel in whole blood digest by ETAAS following on-line coprecipitation-dissolution using the same filterless system as for cadmium. A detection limit of 0.02 pg 1 was reached, making it possible to determine nickel in the blood of unexposed persons. 

The lUPAC (International Union for Pure and Applied Chemistry) reference method for the determination of nickel in serum and urine [43], for example, recommends an acid digestion followed by extraction with APDC-MIBK prior to ETAAS determination. Similar procedures were described for molybdenum in blood plasma which was extracted as the 8-hydroxyquinoline complex prior to its determination by ETAAS [44] and for vanadium in serum and urine [45]. There is no question, however, that these procedures require skilled operators. As multistage manual procedures they also bear the risk of analyte loss and/or contamination, so that the final result may not always reflect the analyte concentration in the original sample. 

Fang and Dong [60] adapted the online coprecipitation preconcentration for ETAAS. They determined cadmium and nickel in digested whole blood. Enrichment factors of 16 and 8 were obtained for cadmium and nickel, respectively, using 20- and 40-sec precipitate collection times at a flow rate of 3 mL/min for cadmium and 2 mL/min for nickel. The detection limits were 0.003 p,g/liter for cadmium and 0.02 ng/liter for nickel. 

N. Carrion, A.M. Itriago, M.A. Alvarez, and E. Eljuri. Simultaneous determination of lead, nickel, tin, and copper in aluminium-base alloys using slurry sampling by electrical discharge and multielement ETAAS. Talanta 61 621-632, 2003. 

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