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AbstractThe paper discusses using sorption preconcentration of elements from mineral waters by graphene oxide. The procedure aims to extract heavy metals such as Cd, Cr, Cu, Pb, Zn and other analytes from solution. Inductively coupled plasma – mass spectrometry (ICP-MS) and inductively coupled plasma – optical emission spectrometry (ICP-OES) were used to determine the analyte content. Graphene oxide was obtained by microwave exfoliation of graphite oxide. The sorption of analytes on the graphene oxide at different pH values and coexisting ion effect were studied in detail. Preliminary preconcentration of analytes provides good extraction recoveries using the optimal conditions. The limits of detection (LODs) of 27 analytes for the developed procedure ranged 0.1 to 200 ng L−1 for ICP-MS and from 5 to 1000 ng L−1 for ICP-OES. Sorption concentration provides recoveries of analytes from 80 to 110%. Graphene oxide was successfully employed for the sorption preconcentration of analytes from mineral and tap water. [ABSTRACT FROM AUTHOR]

The combination of two-jet arc plasma optical emission spectrometry (TJP-OES) and electrothermal vaporization (ETV) for sample introduction is proposed for the first time. The direct analysis of solid tellurium samples by ETV-TJP-OES is described. The temperature program of ETV enabled the evaporation of the sample matrix (tellurium) and analytes separately. The separate vaporization of the sample matrix and analytes reduced interference, which ensured lower limits of detection of the technique (LODs). The proposed ETV-TJP-OES technique allowed the simultaneous determination of up to 17 elements in a high-purity tellurium sample with LODs ranging from 0.02 to 50 ng g−1. The LODs of Al, Au, Ba, Be, Cr, Mg, Mn, Ni, Pb, Re, Sr and Zn provided by ETV-TJP-OES are 2 to 50 times lower compared with inductively coupled plasma optical emission spectrometry (ICP OES) after sample decomposition and analysis using pneumatic nebulization for sample introduction into the ICP. The accuracy of the proposed technique was confirmed by the analysis of tellurium samples by ICP-OES and by analyte (spike) recovery tests. [ABSTRACT FROM AUTHOR]

The paper presents а comparison of analytical performances of inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) for trace analysis of high purity bismuth and bismuth oxide. Matrix effects in the ICP-MS and ICP-AES methods were studied as a function of Bi concentration, ICP power and nebulizer flow rate. For ICP-MS the strong dependence of the matrix effects versus the atomic mass of analytes was observed. For ICP-AES the minimal matrix effects were achieved for spectral lines of analytes with low excitation potentials. The optimum degree of sample dilution providing minimum values of the limits of detection (LODs) was chosen. Both methods let us to reach LODs from n·10 −7 to n·10 −4 wt% for more than 50 trace elements. For most elements the LODs of ICP-MS were lower in comparison to ICP-AES. Validation of accuracy of the developed techniques was performed by “added-found” experiments and by comparison of the results of ICP-MS and ICP-AES analysis of high-purity bismuth oxide. [ABSTRACT FROM AUTHOR]

AbstractA method has been reported for determining of Au and Ag in waters using preliminary sorption concentration of these analytes by microwave exfoliated graphene oxide (GO) and quantitative analysis by two-jet arc plasma atomic emission spectrometry (TJP-AES) and graphite furnace atomic absorption spectrometry (GFAAS). The parameters of sorption of analytes such as duration of sorption and pH were optimized for the preliminary concentration of Au and Ag on various carbon sorbents for subsequent TJP-AES and GFAAS analysis. The sorption properties of carbon nanotubes (CNTs), multilayer graphene (MLG) and GO such as sorption capacity and surface area were compared. The content of analytes in sorption materials was defined. The results demonstrated that GO provides the best sorption properties and the use of exfoliated GO for preconcentration decreaces the blank signal from nonselective absorption by 10 to 120 times. The limits of detection (LODs) for Au and Ag are 4·10−1 µg L−1 and 8·10−2 µg L−1 by GFAAS and 5 µg L−1 and 2·10−1 µg L−1 by TJP-AES. [ABSTRACT FROM AUTHOR]

The paper discusses the development of optical-emission and mass-spectral with inductively coupled plasma (ICP-OES/MS) analysis procedures for determination of traces in cadmium. These procedures are based on the preliminary concentration of traces by selective volatilization of cadmium in vacuum through the film of its own oxide and the subsequent ICP-OES/MS analysis of concentrate. The relative concentration coefficient for the entire array of the experimental data is at least 150. The trace limits of detection (LODs) have been evaluated for the developed ICP-OES and ICP-MS analysis procedures. The ICP-OES method allows to determine 43 traces (Ag, Al, As, Au, B, Ba, Be, Ca, Ce, Co, Cr, Cu, Dy, Er, Fe, Ga, Gd, Hf, Ho, K, La, Li, Lu, Mg, Mn, Mo, Nb, Ni, Pb, Re, Sb, Sm, Sn, Sr, Ta, Tb, Ti, V, W, Y, Yb, Zn, Zr) at the concentration level from 0.1 to 40 ng·g−1. At the same time implementation of the ICP-MS method provides data about 41 impurities (Ag, Al, As, Au, B, Ba, Be, Bi, Ce, Co, Cr, Cu, Dy, Er, Ga, Gd, Hf, Ho, In, La, Lu, Mn, Mo, Nb, Ni, Pb, Re, Sb, Sm, Sn, Sr, Ta, Tb, Te, Ti, V, W, Y, Yb, Zn, Zr) with LODs from 0.002 to 10 ng·g−1. Unlabelled Image • Quality control of high-purity cadmium for electronic application. • Preconcentration of traces using cadmium selective volatilization in vacuum. • Multi-element determination of traces by ICP-OES and ICP-MS. [ABSTRACT FROM AUTHOR]