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1.
Two-dimensional elemental mapping (bioimaging) via laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was performed on 5 μm thick formalin-fixed, paraffin-embedded kidney tissue sections from Cynomolgus monkeys administered with increasing pharmacological doses of cisplatin. Laterally resolved pixels of 1 μm were achieved, enabling elemental analysis on a (sub-)cellular level. Zones of high Pt response were observed in the renal cortex, where proximal tubules are present, the epithelium of which is responsible for partial reabsorption of cisplatin. Histopathological evaluation, of hematoxylin and eosin-stained serial sections, adjacent to the sections probed via LA-ICP-MS, revealed minimal to mild cisplatin-related lesions (<100 μm) in the renal cortex. Necrotic proximal tubules with sloughed epithelial cells in their lumen could be linked directly to the areas with the highest accumulation of cisplatin, indicating a direct link between cellular concentration and toxicity, thereby providing more insight into the mechanisms through which renal damage occurs.  相似文献   
2.
Three different types of simple and low-cost calibration material for the measurement of the metals content of ambient particulate matter (PM) on filters using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) have been compared: cellulose ester filters spiked with multi-element calibration solutions, pellets of compressed ambient particulate matter certified reference material (CRM), and powdered ambient particulate matter CRM adhered to a surface. Elements determined were As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn, each at approximate levels of 1000?ng per filter. Blank filters spiked with multi-elemental standards were found to be significantly more reproducible and repeatable than materials based on powdered reference materials. However, a comparison of these spiked filters with real samples of ambient PM showed that the analytical sensitivities obtained per mass of analyte were significantly different. It is concluded that the spiked filters could act as very effective quality control standards correcting, to within 1%, drifts in LA-ICP-MS measurements of up to 10%, or as indirect calibration materials supported by additional measurements using traditional wet chemical techniques.  相似文献   
3.
Laser-ablation based analytical techniques represent a simple way for fast chemical analysis of different materials. In this work, an exploratory study of multi-element (Ca, Al, Fe, Mn) mappings of a granite sample surface was performed by laser-induced breakdown spectroscopy (LIBS) and subsequently by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis. The operating parameters (e.g. pulse energy, ablation-crater size) were optimized for both techniques in order to achieve the appropriate conditions for two-dimensional high-resolution compositional mappings of mineral microstructures in large sample areas. The sample was scanned with 100 × 100 individual sample points to map an area of 20 × 20 mm2. The normalized signals were used for construct of contour plots which were colored according local distribution of the selected elements. The results of two laser-based methods were compared and found to be similar.  相似文献   
4.
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), micro X-ray fluorescence spectroscopy (μXRF), and laser induced breakdown spectroscopy (LIBS) are compared in terms of discrimination power for a glass sample set consisting of 41 fragments. Excellent discrimination results (> 99% discrimination) were obtained for each of the methods. In addition, all three analytical methods produced very similar discrimination results in terms of the number of pairs found to be indistinguishable. The small number of indistinguishable pairs that were identified all originated from the same vehicle. The results also show a strong correlation between the data generated from the use of µXRF and LA-ICP-MS, when comparing µXRF strontium intensities to LA-ICP-MS strontium concentrations. A 266 nm laser was utilized for all LIBS analyses, which provided excellent precision (< 10% RSD for all elements and < 10% RSD for all ratios, N = 5). The paper also presents a thorough data analysis review for forensic glass examinations by LIBS and suggests several element ratios that provide accurate discrimination results related to the LIBS system used for this study. Different combinations of 10 ratios were used for discrimination, all of which assisted with eliminating Type I errors (false exclusions) and reducing Type II errors (false inclusions). The results demonstrate that the LIBS experimental setup described, when combined with a comprehensive data analysis protocol, provides comparable discrimination when compared to LA-ICP-MS and μXRF for the application of forensic glass examinations. Given the many advantages that LIBS offers, most notably reduced complexity and reduced cost of the instrumentation, LIBS is a viable alternative to LA-ICP-MS and μXRF for use in the forensic laboratory.  相似文献   
5.
采用自制的大气压下介质阻挡放电装置串联在激光剥蚀池与ICP炬管之间, 对激光剥蚀产生的气溶胶进行预电离. 结果表明, 元素瞬时信号轮廓的平滑度得以改善, 元素分析信号精密度(RSD, n=3)可提高2.55%. 在ArF准分子激光(193 nm)和Nd∶YAG 固体激光(213 nm)两种不同波长的激光剥蚀系统中, 元素分馏因子均比常规模式下更接近于1, 表明采用介质阻挡放电对气溶胶预电离后元素分馏效应得以有效抑制. 相比两种不同波长的激光剥蚀系统, 介质阻挡放电对213 nm固体激光的元素分馏效应改善作用明显.  相似文献   
6.
Visualization of elemental distributions in thin sections of biological tissue is gaining importance in many disciplines of biological and medical research. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and scanning micro-X-ray fluorescence spectrometry (micro-XRF) are two widely used microanalytical techniques for elemental mapping. This article compares the capabilities of the two techniques for imaging the distribution of selected elements in the model organism Daphnia magna in terms of detection power and spatial resolution. Sections with a thickness of 10 and 20 μm of the fresh water crustacean Daphnia magna were subjected to LA-ICP-MS and micro-XRF analysis. The elemental distributions obtained for Ca, P, S and Zn allow element-to-tissue correlation. LA-ICP-MS and micro-XRF offer similar limits of detection for the elements Ca and P and thus, allow a cross-validation of the imaging results. LA-ICP-MS was particularly sensitive for determining Zn (LOD 20 μg g−1, 15 μm spot size) in Daphnia magna, while the detection power of micro-XRF was insufficient in this context. However, LA-ICP-MS was inadequate for the measurement of the S distributions, which could be better visualized with micro-XRF (LOD 160 μg g−1, 5 s live time). Both techniques are thus complementary in providing an exhaustive chemical profiling of tissue samples.  相似文献   
7.
Müller G  Stahnke F  Bleiner D 《Talanta》2006,70(5):991-995
Laser-assisted plasma spectrometry is a palette of analytical techniques (L-OES, LA-ICP-MS) capable of fast spatially-resolved elemental analysis in the micrometer range. For fast estimation of the occurrence in steel samples of non-metallic inclusions, which degrade the material's technical properties, simultaneous OES detection and sequential ICP-MS detection were compared. Histograms were obtained for the intensity distribution of the acquired signals (laser pulse statistics). The skewness coefficient of the histograms for Al (indicator of non-metallic inclusions) was found to be clearly dependent on the fraction of non-metallic inclusions in the case of scanning L-OES. For LA-ICP-MS less clear dependence was observed, which was influenced by the acquisition characteristics. In fact, less measurement throughput limited for LA-ICP-MS the counting statistics to an extent that overrides the benefit of higher detection power as compared to L-OES.  相似文献   
8.
The spatial distribution and concentration of impurities in metallurgical-grade silicon (MG-Si) samples (97–99% w/w Si) were investigated by use of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The spatial resolution (120 μm) and low limits of detection (mg kg−1) for quality assurance of such materials were studied in detail. The volume-dependent precision and accuracy of non-matrix-matched calibration for quantification of minor elements, using NIST SRM 610 (silicate standard), indicates that LA-ICP-MS is well suited to rapid process control of such materials. Quantitative results from LA-ICP-MS were compared with previously reported literature data obtained by use of ICP-OES and rf-GD-OES. In particular, the distribution of element impurities and their relationship to their different segregation coefficients in silicon is demonstrated. Dedicated to Professor Klaus G. Heumann  相似文献   
9.
Homogeneous doped ZnO nanoparticles were synthesised by the Pechini method. A statistical experimental design was used to study the effects of the synthesis method variables on the particle size. The variables were the molar ratios of the reagents and the calcination temperature. The results indicated that the calcination temperature was the only factor that had a significant effect on the particle size. The particle size of ZnO varied between 16 and 76 nm with calcination temperatures of 400–800 °C. The homogeneity was studied by the ICP-MS technique, and the powders were found to be highly homogeneous.  相似文献   
10.
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used for the quantitative imaging of Cu and other essential elements (such as K, Mg, Mn, P, S and B) in the leaves of a Cu-tolerant plant Elsholtzia splendens treated with the enriched 65Cu isotope tracer (isotope abundance of 89.2%). The leaves (newly formed, fully grown and oldest) were scanned directly with a focused Nd:YAG laser in the laser ablation chamber. The ablated material was transported with argon as carrier gas to a quadrupole-based ICP-MS (ICP-QMS), and the ion intensities of 65Cu+, 39K+, 24Mg+, 55Mn+, 31P+, 34S+ and 11B+ were measured by ICP-QMS to study the accumulation of Cu and other elements of interest. Standard reference material NIST SRM 1515 Apple Leaves doped with known concentrations of analytes (from 0.1 to 2000 mg L−1) was measured together with the samples by LA-ICP-MS and was used for the quantification of the analytical data. Notable accumulation of Cu in the newly formed leaves was clearly identified by imaging LA-ICP-MS. The increased isotope ratios of 65Cu/63Cu measured by LA-ICP-MS demonstrated the path of Cu uptake and accumulation via the petiole and main veins in the leaves. Cu stress-induced accumulation of K, Mg, Mn, P and S in the newly formed leaves was observed, while B was not significantly affected. In the present study, the concentrations of K, Mg, Mn, P and S were not obviously changed in the fully grown leaves after short-term treatment. Along with the treatment, a visible decrease of K and P was found in the oldest leaves, while other elements were not influenced by Cu stress.  相似文献   
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