A fast method for multi-metal determination in soil samples by high-resolution inductively-coupled plasma-mass spectrometry (HR–ICP–MS)

Abstract

Methods for multi-elemental quantitative analysis of soil samples by high-resolution inductively-coupled plasma-mass spectrometry (HR–ICP–MS) with preceding one-step wet digestion in a high-pressure microwave system have been developed. The application of aqua regia as a reagent for wet digestion using a high-pressure microwave digestion system, followed by determination using HR–ICP–MS, allows an accurate, simultaneous determination of a large number of heavy metals and metalloids that are considered as potentially hazardous for the environment and health. The values of the concentrations of the elements in the analysed certified reference material (CRM) that have been obtained in this study can be used as indicative values where this CRM is used as a control for the quality of the measurements.     

Multianalysis of trace elements in mosses with inductively coupled plasma-mass spectrometry

As a part of an air-pollution biomonitoring survey, a procedure using inductively coupled plasma-mass spectrometry (ICP-MS) and microwave digestion was developed to achieve a high sample throughput and guarantee the accuracy of the results. This article presents an analytical method to measure 22 trace elements. As, Ba, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Ni, Pb, Rb, Sb, Sr, Th, Tl, U, V, W were analyzed in 563 mosses collected in France. The digestion was performed in polytetrafluoroethylene (PTFE) vessel using the mixture HNO₃-H₂O₂-HF. The data were reprocessed taking into account the drift curve calculated for each element. The detection limits (DL) calculation was based on the standard deviations of the reagent blanks concentrations. The DL varied from one batch to another, because of the heterogeneity of the mosses’ elemental contents. The DL ranged between 0.001 μg/g (Cs, Tl) and 70 μg/g (Fe) and were mainly around 0.01 μg/g (As, Cd, Ce, Co, Hg, La, Mo, Sb, Sr, U, V, W). The detection limits obtained were in agreement with the concentrations observed in the samples, except for Hg and Ni. The reproducibility between duplicates and the analytical precision were near 10%. The procedure was tested with the mosses’ reference materials.     

Crystal structure of the carboxyltransferase domain of the oxaloacetate decarboxylase Na+ pump from Vibrio cholerae

Oxaloacetate decarboxylase is a membrane-bound multiprotein complex that couples oxaloacetate decarboxylation to sodium ion transport across the membrane. The initial reaction catalyzed by this enzyme machinery is the carboxyl transfer from oxaloacetate to the prosthetic biotin group. The crystal structure of the carboxyltransferase at 1.7 A resolution shows a dimer of alpha(8)beta(8) barrels with an active site metal ion, identified spectroscopically as Zn(2+), at the bottom of a deep cleft. The enzyme is completely inactivated by specific mutagenesis of Asp17, His207 and His209, which serve as ligands for the Zn(2+) metal ion, or by Lys178 near the active site, suggesting that Zn(2+) as well as Lys178 are essential for the catalysis. In the present structure this lysine residue is hydrogen-bonded to Cys148. A potential role of Lys178 as initial acceptor of the carboxyl group from oxaloacetate is discussed.     

Element bioimaging of liver needle biopsy specimens from patients with Wilson’s disease by laser ablation-inductively coupled plasma-mass spectrometry

A laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS) method is developed and applied for the analysis of paraffin-embedded liver needle biopsy specimens of patients with Wilson’s disease (WD), a rare autosomal recessive disorder of the copper metabolism causing various hepatic, neurological and psychiatric symptoms due to a copper accumulation in the liver and the central nervous system. The sample set includes two WD liver samples and one negative control sample. The imaging analysis was performed with a spatial resolution of 10 μm. Besides copper, iron was monitored because an elevated iron concentration in the liver is known for WD. In addition to this, both elements were quantified using an external calibration based on matrix-matched gelatine standards. The presented method offers low limits of detection of 1 and 5 μg/g for copper and iron, respectively. The high detection power and good spatial resolution allow the analysis of small needle biopsy specimen using this method. The two analyzed WD samples can be well differentiated from the control sample due to their inhomogeneous copper distribution and high copper concentrations of up to 1200 μg/g. Interestingly, the WD samples show an inverse correlation of regions with elevated copper concentrations and regions with high iron concentrations.     

Determination of platinum in rat dorsal root ganglion using ICP-MS

This study evaluated the performance of inductively coupled plasma mass spectrometry for the determination of platinum (Pt) in rat dorsal root ganglion. The method detection limit was found to be 0.008 ng/mL of Pt, which corresponds to 4 pg of Pt per milligram of ganglia. The standard deviations in the tissue matrix were 5.7% or better and minimum matrix effect was observed. Compared to indium, the use of iridium or a combination of iridium and bismuth as internal standard(s) provided more accurate measurement. The Pt in the tissue digestate was stable for a minimum of 46 d at levels above 0.05 ng/mL. Flow injection analysis using undiluted digestates resulted in approximately 20% signal enhancement. Internal standard correction was necessary to obtain accurate results. The method was used in initial studies in which rats were dosed with cisplatin and has shown that Pt accumulates and persists in dorsal rat ganglion following treatment. Paper presented at the Pittsburgh Conference, Atlanta, GA, March 1997     

Assessment of the contamination from devices used for sampling and storage of whole blood and serum for element analysis

An assessment of potential contamination risk associated with devices routinely used in hospitals and clinical laboratories for sampling and storage of whole blood and serum was made by analysis of leachates from the devices. The devices checked were disposable stainless steel needles, different types of blood collection tubes; serum separation tubes, disposable plastic pipettes and plastic vials used for serum storage. Concentrations of about 70 elements in solution after leaching with 0.05 mol l(-1) HNO3 were determined by double focusing sector field inductively coupled plasma mass spectrometry (sector field ICP-MS). For the elements present in blood/serum at concentrations higher than 10 ng ml(-1) (Na, Ca, Mg, P, Fe, Br, Si, Zn, Cu, Rb, Se and I) contribution from devices was as a rule negligible (less than 1% of expected concentrations in the body fluids), but for the majority of trace and ultra-trace elements it may significantly affect or even prevent accurate determination. The highest trace element contribution was found to derive from commercially available blood collection and serum separation tubes. Apparent concentrations of Al, Ba, Th, rare earth, and some other elements resulting from contamination were higher than normal serum concentrations all types of tubes tested for.     

Fractionation of heavy metals in contaminated soils surrounding non-ferrous metals smelting area in the North China Plain

Abstract

The accumulation of heavy metals in soil is a serious environmental problem. The risk of metals in soil is associated critically with their species. Operationally determined speciation analysis of Cr, Mn, Ni, Cu, Zn, Sb, Cd and Pb was carried out in the area of non-ferrous metals-smelting in the North China Plain, using inductively coupled plasma-mass spectroscopy after sequential chemical extraction. The average potential mobility fraction was calculated. The average potential mobility of the metals had the following order: Cd(44.7%) > Pb(29.6%) > Mn(14.8%) > Zn(12.5%) > Cu(5.9%) > Sb(5.0%) > Ni(2.1%) > Cr(0.8%). It is concluded that there is a distinct spatial heterogeneity in the concentration of heavy metals in the studied area. The results indicate that the polluting heavy metals, in particular Cd and Pb, have high potential mobility.     

基于电感耦合等离子体质谱的蛋白质定量技术研究进展

综述了ICP-MS法应用于蛋白质定量技术方面的研究进展.蛋白质定量研究已成为蛋白质组学研究领域的热点,它是解析生物体蛋白质功能的重要途径.基于同位素标记和生物质谱分析技术是蛋白质定量最常用的方法之一,近年来,随着质谱技术的发展,电感耦合等离子体质谱(ICP-MS)技术成为元素测量的重要手段,这使其在蛋白质定量中具一定的应用前景.     

Correlations of trace element levels within and between different normal autopsy tissues analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES)

Imbalance in trace metal metabolism may lead to metal interactions that may be of patho-physiological importance. Knowledge of the relation between trace metals in normal tissues is needed to assess abnormal deviations associated with disease. In this study correlations between Cu, Co, Cr, Fe, Mn, Ni, Se, Zn, Al, Ba, Cd, Pb and Sr within the same and between 6 different, normal autopsy tissues were determined using Spearman rank correlation analysis based on analytical data obtained by inductively coupled plasma atomic emission spectrometry (ICP-AES). Fe-Co were correlated in most tissues. Cu-Mn, Zn-Cu, Zn-Mn and Zn-Cd were highly correlated in the kidney medulla. Ni-Ni, Sr-Sr and Cd-Cd were correlated between several tissues, while Fe-Fe, Zn-Zn and Cu-Cu were correlated between kidney cortex and medulla. Mn-Mn was highly correlated between the liver and brain front lobe, cerebellum and heart. High correlations were found for Ni-Co and for Se-Mn between the kidney cortex and brain front lobe and pancreas respectively. Inverse correlations were found for Se-Cd between kidney cortex and cerebellum, for Se-Cd and Cd-Zn between kidney medulla and heart, for Co-Sr and Fe-Sr between the liver and kidney cortex and heart respectively, and for Sr-Mn between kidney medulla and pancreas. A large number of trace elements are statistically correlated within and between different, normal tissues. Knowledge of these correlations may contribute to increase the understanding of kinetic interactions of trace metals in the body and the role of such interactions in normal and disturbed trace metal metabolism.     

Studies on some trace and minor elements in blood

Blood is one of the widely used specimens for biological trace element research because of its biological significance and ease of sampling. We have conducted a study of the blood of the Kalpakkam township population for trace and minor elements. For this purpose, analytical methods have been developed and standardized in our laboratory for the elemental analysis of blood plasma and red cells. Inductively coupled plasma-mass spectrometry (ICP-MS), a relatively new technique, has been applied for the analysis of trace elements. Details regarding spectral interference and matrix interference encountered in the analysis of blood and the methods of correcting them have been discussed. Flame atomic absorption spectrometry (AAS)/atomic emission spectrometry (AES) has been applied for the determination of minor elements. Precision and accuracy of these methods have also been discussed.