Fractionation of Cd and Pb in BCR No. 601 sediment reference material following the BCR protocol for sequential extraction and determination by electrothermal atomic absorption spectrometry using permanent modifiers

Comparative efficacy of platinum group metal modifiers in electrothermal atomic absorption spectrometry

“…Although mixtures of PGMs sometimes provide higher modification efficiency compared to that of the corresponding individual components, this is not the case for the determination of lead [48,61]. Enhancement of the efficiency was obtained when using tungsten carbide together with lowvolatility PGMs as permanent modifiers.…”

“…Bulska et al [118] obtained the best results for the determination of silicon in serum when a mixture of prereduced Pd and Rh modifiers was used. The mixed Rh+Ir permanent modifier studied by da Silva et al [21] and Giacomelli et al [38,61] was sometimes more efficient than the individual PGM modifiers. However, for the determination of As, In and Se in a sulphate medium [33], the efficiency of mixtures of pre-reduced PGM modifiers was not enhanced over that of palladium, which was the best modifier for this system.…”

“…Better analytical characteristics were obtained with Ru+ZrC compared with permanent Ru and Pd+Mg(NO 3 ) 2 regular modifiers. [64] As a rule, the efficiency of mixtures of PGMs as permanent modifiers is comparable to that of individual PGMs [21,55,59,61]. However, for the determination of cadmium in complex samples, the choice of a permanent modifier may be refractory PGM (Rh, Ru or Ir) deposited on a tungsten carbide-modified graphite surface [35,57,64].…”

Electrothermal atomic absorption spectrometric determination of cadmium and lead in environmental, botanic and biological samples by different permanent modifiersElectronic supplementary information (ESI) available: Temperature program for modifier coating; optimization of mass and mass ratio of permanent modifiers and cadmium peak profiles; pyrolysis temperatures; characteristic masses and detection limits of cadmium and lead; and contents and recoveries of cadmium and lead in various reference materials.

“…The main observed advantages such as faster heating programs, better detection limits and longer term signal stability have been described in earlier studies. [1][2][3][4][5][6][7][8][9][10][11][12][13] A procedure for permanent chemical modification consists of the introduction of several aliquots of the chemical modifier solution into the graphite platform, followed by stepwise drying-pyrolysis, thereby obtaining a layer of the modifier thermally deposited on the graphite surface. [3][4][5] The Rh, Ru and Ir, as well as carbide forming elements such as Zr and W, have been used as permanent modifiers for the determinations of analytes in various matrices.…”

“…[3][4][5] The Rh, Ru and Ir, as well as carbide forming elements such as Zr and W, have been used as permanent modifiers for the determinations of analytes in various matrices. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] The aims of this work are to evaluate the difference in performance of Zr, W, Ru, Zr-Ru and Zr-W and to compare with Pd 1 Mg(NO 3 ) 2 for the determination of cadmium and lead in environmental, botanic and biological samples by ETAAS. The evaluation of the Zr-W or Zr-Ru was performed in order to attain at least the same selectivity as Pd 1 Mg(NO 3 ) 2 [3][4][5] for overcoming interferences in the samples.…”