激光剥蚀电感耦合等离子体质谱新进展

简单介绍了激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)的基本原理及装置。分别对LA-ICP-MS在飞秒激光器、紫外激光器、固液气溶胶混合进样、集合式小样品标样、原位统计分布技术上的技术新进展进行了详细的评述。最后对LA-ICP-MS在元素含量分析与空间分布分析中所占的地位及其应用前景进行了展望。     

激光剥蚀电感耦合等离子体质谱法分析Cr∶ZnSe晶体中掺杂元素Cr的含量和分布

采用激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)法研究激光晶体材料Cr∶Zn Se晶体中掺杂元素铬(Cr)的含量和分布。利用镀膜扩散掺杂方法,制备不同掺杂浓度的Cr∶Zn Se晶体标准样品作为固体标准物质,实现Cr∶Zn Se晶体中Cr的定量分析。LA-ICP-MS法研究自制标准样品中Cr的分布均匀性,电感耦合等离子体光谱法测定其准确含量。通过激光点剥蚀和线扫描剥蚀采样,获得Cr元素的点位和含量分布信息,实现晶体中Cr的原位微区分析。标准工作曲线相关系数0.9992,检出限0.08 mg/kg。本方法可为不同生长条件下Cr∶Zn Se晶体中Cr的统计分布分析提供有效检测手段。     

同位素稀释-激光剥蚀-电感耦合等离子体质谱法测定生物组织样品中铁元素的含量

针对目前采用同位素稀释-激光剥蚀-电感耦合等离子体质谱(ID-LA-ICP-MS)对固体生物组织切片样品难以实现原位准确定量的难题,本研究将同位素稀释法与LA-ICP-MS技术相结合,通过开展生物组织样品与浓缩稀释剂的同位素充分交换平衡、稀释剂添加方式、原位的同位素比测量等关键技术研究,确定了组织切片与同位素稀释剂的最佳平衡时间、稀释剂的质量以及选用甲醇作为稀释剂溶剂等实验条件,建立了基于同位素稀释技术的LA-ICP-MS技术在生物样品组织切片中Fe元素的微区定量分析方法,并采用实验室自行制备的均匀的山羊脑和牛肝组织切片标准样品对方法进行了验证,通过ID-LA-ICP-MS方法的测量结果与微波消解-同位素稀释方法的测量结果相一致,验证了该方法的有效性和可靠性。本方法可进一步应用于临床中生物组织切片样品中金属元素的原位、微区定量测量及成像分析。     

激光剥蚀电感耦合等离子体质谱法测定地质玻璃中铅同位素组成

将193nm准分子纳秒激光与四级杆电感耦合等离子体质谱联用,测量了国际参照物玻璃中Pb同位素丰度比。通过剥蚀NIST612,USGS和MPI-DING玻璃,探讨了利用激光剥蚀电感耦合等离子体质谱直接测定固体样品铅同位素比值的精密度及其适用范围。通过扣除Ar载气中204Hg对204Pb的同量异位素干扰,采用内标法和外标法校正LA-ICP-MS仪器的质量歧视效应,获得的206Pb/204Pb、207Pb/204Pb、208Pb/204Pb同位素比值测量的相对误差小于±1.2%,207Pb/206Pb、208Pb/206Pb同位素比值测定的相对误差小于±0.8%。对比结果表明,采用内标法校正的结果更接近真实值。测定的Pb同位素比值的精密度与样品中Pb含量密切相关,对Pb含量大于40μg/g的样品,同位素比值206Pb/204Pb、207Pb/204Pb、208Pb/204Pb的RSD在1.0%以内,207Pb/206Pb、208Pb/206Pb的RSD在0.5%以内。大气颗粒物样品中Pb含量很高,采用LA-ICP-MS测定Pb同位素比值,能够鉴别污染来源,满足示踪的要求。     

电感耦合等离子体质谱技术在环境领域的应用

综述电感耦合等离子体质谱技术在环境监测和环境科学研究领域的应用.介绍了电感耦合等离子体质谱技术在环境监测中的分析优势,环境研究领域中稳定同位素比值测定技术及其与色谱、激光烧蚀、流动注射技术联用分析技术应用的进展.     

193nm激光器与电感耦合等离子体质谱仪联用条件优化研究

激光剥蚀电感耦合等离子体质谱仪( LA-ICP-MS)是采用激光剥蚀固体进样方式构建的新型等离子体质谱分析仪器.由于受激光产生原理-“脉冲式激发”的限制,样品的剥蚀进样过程属于间歇模式.因而激光剥蚀系统与电感耦合等离子体质谱仪联机分析结果的相对标准偏差( RSD)通常达10％以上,影响数据的分析精度.本设计在激光剥蚀系...     

基于激光剥蚀-电感耦合等离子体质谱技术的生物元素成像分析

生物体内的微量元素具有十分重要的生物功能,也与许多疾病密切相关。现代生物医学的研究亟需能在组织、细胞等不同水平上原位分析生物样品中微量元素的分析方法。本研究建立了激光剥蚀-电感耦合等离子体质谱( LA-ICP-MS)原位分析生物样品的方法。采用线扫描模式和较小的激光输出能量(﹤1 J/cm2),得到了鼠脑切片和金纳米颗粒暴露后单细胞的金属元素成像图。 LA-ICP-MS具有空间分辨率高、检出限好、运行成本较低等优势,有望在生物医学研究中得到更广泛的应用,发挥更重要的作用。     

电感耦合等离子体质谱激光烧蚀固体进样技术新进展

本文简单地介绍了电感耦合等离子体质谱(LA-ICP-MS)的基本原理及装置。分别对LA-ICP-MS在飞秒激光器、紫外激光器、固液气溶胶混合进样、集合式小样品标样、原位统计分布技术上的技术新进展进行了详细的评述。     

飞秒激光剥蚀-多接收等离子体质谱原位分析玄武岩玻璃样品Mg同位素组成

建立了飞秒激光剥蚀多接收等离子体质谱(fsLA-MC-ICP-MS)原位微区分析玄武岩玻璃中Mg同位素的方法.溶液进样-干气溶胶条件下浓度匹配实验表明,样品和标准样品中Mg浓度比在0.4 ～3.0时,可获得准确样品Mg同位素组成.激光剥蚀条件对Mg同位素的准确测定有明显的影响,激光剥蚀斑束和扫描速率变化,使得质谱仪的质量歧视效应随进样负载量不同而产生较大的变化,并影响样品Mg同位素组成;激光剥蚀频率与δ25 Mg正相关,与δ26 Mg负相关,当剥蚀频率大于4 Hz时,δ25 Mg和δ26 Mg趋于平稳;超快激光的能量密度对Mg同位素组成影响较小.利用本方法对国际标准样品的分析结果与参考值在误差范围内一致.本方法具有制样简单、快速的特点,且测试结果准确可靠,为火山玻璃中Mg同位素分析提供了有效的分析手段.     

激光剥蚀电感耦合等离子体质谱在生物样品定量分析中的研究进展

激光剥蚀-电感耦合等离子体质谱(LA-ICP-MS)作为一种可以直接分析固体材料的元素含量和同位素比值的分析技术,已经历了30多年的迅速发展。本文首先简要介绍了LA-ICP-MS的仪器装置,之后阐述了LA-ICP-MS定量分析中的基体效应、分馏效应以及定量校正方法,重点介绍了其在生物医学研究中的应用。最后对LA-ICP-MS的发展方向和应用前景进行了展望。     

激光剥蚀电感耦合等离子体质谱微区分析新进展

从仪器、基础研究诸方面评述近年来LA-ICP-MS微区分析进展,重点介绍了与ICP-MS联用的激光技术发展、校正方法、分馏效应、剥蚀颗粒分布研究及仪器装置与实验技术与改进,对LA-ICP-MS技术的应用作了回顾与展望。     

Imaging of metals in biological tissue by laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS): state of the art and future developments

Laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) is well established as a sensitive trace and ultratrace analytical technique with multielement capability for bioimaging of metals and studying metallomics in biological and medical tissue. Metals and metalloproteins play a key role in the metabolism and formation of metal‐containing deposits in the brain but also in the liver. In various diseases, analysis of metals and metalloproteins is essential for understanding the underlying cellular processes. LA–ICP–MS imaging (LA–ICP–MSI) combined with other complementary imaging techniques is a sophisticated tool for investigating the regional and cellular distribution of metals and related metal‐containing biomolecules. On the basis of successful routine techniques for the elemental bioimaging of cryosections by LA–ICP–MSI with a spatial resolution between 200 and ~10 µm, the further development used online laser microdissection ICP–MSI to study the metal distribution in small biological sample sections (at the cellular level from 10 µm to the submicrometer range). The use of mass spectrometric imaging of metals and also nonmetals is demonstrated on a series of biological specimens. This article discusses the state of the art of bioimaging of metals in thin biological tissue sections by LA–ICP–MSI with spatial resolution at the micrometer scale, future developments and prospects for quantitative imaging techniques of metals in the nanometer range. In addition, combining quantitative elemental imaging by LA/laser microdissection–ICP–MSI with biomolecular imaging by matrix‐assisted laser desorption/ionization–MSI will be challenging for future life science research. Copyright © 2013 John Wiley & Sons, Ltd.     

电感耦合等离子体-质谱联用及其在环境和生物样品中铂族金属分析的应用进展

本文简述了电感耦合等离子体-质谱联用(LCP-MS)技术和仪器的发展,分析了环境和生物样品中铂族金属分析的主要困难,综述了90年代以来国内外ICP-MS技术在环境和生物样品中铂族金属分析的最新进展,引用文献47篇.     

电感耦合等离子体质谱方法在生物样品分析中的应用

介绍了电感耦合等离子体质谱方法在生物样品分析中应用研究的新进展。针对ICP－MS的特点阐述了样品处理、进样方式、干扰校正的主要方法和应注意的问题。     

Lead determination in whole blood by laser ablation coupled with inductively coupled plasma mass spectrometry

This work describes a simple procedure for blood lead level determination. The proposed method requires little sample pretreatment and subsequent direct analysis of a dried blood spot on a filter membrane using laser ablation coupled with inductively coupled plasma mass spectrometry (LA-ICP-MS). In general, LA-ICP-MS studies are somewhat limited by the lack of matrix-matched standards for calibration purposes. Here we describe aqueous standard calibration and matrix-matched calibration methods. This method was validated by analysis of the reference materials. With the matrix-matched calibration method, the recovery ranged from 97.8% to 112.8%, while the aqueous standard calibration method ranged 90.4% to 122.4%. The lower detection limit was estimated as 0.1 ng mL⁻¹. The determination precision, expressed as the relative standard deviation (RSD), was not worse than 10% for all results. A sample throughput of approximately 5 min per sample made it possible to rapidly screen a large number of samples.     

Investigation on elemental and isotopic fractionation during 196 nm femtosecond laser ablation multiple collector inductively coupled plasma mass spectrometry

Despite the large number of successful applications of laser ablation, elemental and isotopic fractionation coupled to inductively coupled plasma mass spectrometry (ICP-MS) remain as the main limitations for many applications of this technique in the fields of analytical chemistry and Earth Sciences. A substantial effort has been made to control such fractionations, which are well-established features of nanosecond laser ablation systems. Technological advancements made over the past decade now allow the ablation of solids by femtosecond laser pulses in the deep ultraviolet (UV) region at wavelengths less than 200 nm. Here the use of femtosecond laser ablation and its effects on elemental and isotopic fractionation is investigated. The Pb/U system is used to illustrate elemental fractionation and stable Fe isotopes are used to illustrate isotopic fractionation. No elemental fractionation is observed beyond the precision of the multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) measurements. Without a matrix match between standard and sample, elemental fractionation is absent even when using different laser ablation protocols for standardization and samples (spot versus raster). Furthermore, we found that laser ablation-induced isotope ratio drifts, commonly observed during nanosecond laser ablation, are undetectable during ultraviolet femtosecond laser ablation. So far the precision obtained for Fe isotope ratio determinations is 0.1‰ (2 standard deviation) for the ⁵⁶Fe/⁵⁴Fe ratio. This is close to that obtainable by solution multiple-collector inductively coupled plasma mass spectrometry. The accuracy of the results appears to be independent of the matrix used for standardization. The resulting smaller particle sizes reduce fractionation processes. Femtosecond laser ablation carries the potential to solve some of the difficulties encountered during the two prior decades since the introduction of laser ablation.     

多接收器电感耦合等离子体质谱方法的开发和应用进展

稳定同位素分析是分析化学一项颇具前景的分支,通过精确测定物质的稳定同位素比值,可以追溯物质来源并探究其转化过程。高精度稳定同位素分析技术的进步依赖于新一代质谱仪的不断发展。其中,多接收器电感耦合等离子体质谱(MC-ICP-MS)是近年发展迅速的一种同位素组成测定工具。稳定同位素分析对样品基质十分敏感,复杂基质能严重干扰同位素测定的精密度和准确度。这对MC-ICP-MS的样品净化提出了极高要求,目前也是同位素分析领域的热点问题。该文聚焦于近年来MC-ICP-MS在样品净化及仪器联用方法方面的相关研究进展,并展望了MC-ICP-MS稳定同位素分析的应用前景。     

激光剥蚀-多接收电感耦合等离子体质谱法 测定含钚颗粒物中240 Pu/239 Pu比值

为高精度、准确地获取含钚颗粒物中具有核保障监督意义和核取证价值的钚同位素比值,建立了激光剥蚀-多接收电感耦合等离子体质谱(LA-MC-ICP-MS)测定含钚颗粒物中240 Pu/239 Pu的分析方法.采用检漏、安装排风罩和擦拭剥蚀池内壁等方式有效降低激光剥蚀产物沾污实验室和危及人身安全的潜在风险.联用扫描电迁移率粒径谱仪(SMPS)与激光剥蚀-多接收器等离子体质谱(LA-MC-ICP-MS)研究了激光剥蚀玻璃基体标样产生气溶胶的分布特性,结果表明,剥蚀产物的主要粒径是40~500 nm,应尽量采用水平管道连接激光剥蚀进样系统与MC-ICP-MS,含钚颗粒物分析后剥蚀池持续吹扫时间应大于15 min.采用外标归一化法离线校正质量分馏效应和离子计数器检测效率,建立了含钚颗粒物中240 Pu/239 Pu的LA-MC-ICP-MS分析方法,固定束斑直径30μm、脉冲重复率5 Hz、剥蚀时间5 s,调节能量密度使含钚颗粒物模拟样品中239 Pu的信号强度分别达2×104 cps和2×105 cps,本方法对240 Pu/239 Pu测量的相对实验标准不确定度小于1.4%(n=6),测量结果与参考值的相对偏差小于4.7%,仪器调试时间和单个样品测量时间分别为9.0和0.5 h.含钚颗粒物模拟样品分析结果表明,本方法精度高、结果准确、分析速度快,可满足核保障监督、禁产核查和核取证中含钚颗粒物直接分析的需求.     

A new laser ablation system for quantitative analysis of solid samples with ICP-MS.

The laser ablation (LA) method is an effective technique for quantitative analysis. In the present work, a new LA system was developed for the high-sensitivity analysis of metal materials using inductively coupled plasma mass spectrometry (ICP-MS). This system consists of a high-frequency Q-switched laser and 2 scanning mirrors for scanning the ablation spot in an adequately large area of the specimen without vacant spaces. The influence of elemental fractionation (non-stoichiometric generation of vapor species) can be eliminated by repetitive irradiation of this pattern on the same area. Particles generated with an average laser power of 0.6 W with the developed LA system gave intensity and stability substantially similar to that of a 500 microg/ml solution steel sample in solution ICP-MS. The analytical performance of the developed LA-ICP-MS was compared with that of a solution ICP-MS using NIST steel SRMs. The performance of the newly-developed system is comparable to that of conventional solution ICP-MS in both accuracy and precision. The correlation coefficients between the contents and the intensity ratios to Fe were over 0.99 for most elements. The relative standard deviation (RSD) obtained by LA-ICP-MS revealed that this system can analyze iron samples with good precision. The results of ultra trace level analysis of high-purity iron showed that developed LA-ICP-MS is capable of analyzing ppm concentration levels with a 20 - 30 ppb level standard deviation. The detection limit was on the order of 10 ppb for most elements.     

Development of routines for simultaneous in situ chemical composition and stable Si isotope ratio analysis by femtosecond laser ablation inductively coupled plasma mass spectrometry

Stable metal (e.g. Li, Mg, Ca, Fe, Cu, Zn, and Mo) and metalloid (B, Si, Ge) isotope ratio systems have emerged as geochemical tracers to fingerprint distinct physicochemical reactions. These systems are relevant to many Earth Science questions. The benefit of in situ microscale analysis using laser ablation (LA) over bulk sample analysis is to use the spatial context of different phases in the solid sample to disclose the processes that govern their chemical and isotopic compositions. However, there is a lack of in situ analytical routines to obtain a samples' stable isotope ratio together with its chemical composition. Here, we evaluate two novel analytical routines for the simultaneous determination of the chemical and Si stable isotope composition (δ³⁰Si) on the micrometre scale in geological samples. In both routines, multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) is combined with femtosecond-LA, where stable isotope ratios are corrected for mass bias using standard-sample-bracketing with matrix-independent calibration. The first method is based on laser ablation split stream (LASS), where the laser aerosol is split and introduced simultaneously into both the MC-ICP-MS and a quadrupole ICP-MS. The second method is based on optical emission spectroscopy using direct observation of the MC-ICP-MS plasma (LA-MC-ICP-MS|OES). Both methods are evaluated using international geological reference materials. Accurate and precise Si isotope ratios were obtained with an uncertainty typically better than 0.23‰, 2SD, δ³⁰Si. With both methods major element concentrations (e.g., Na, Al, Si, Mg, Ca) can be simultaneously determined. However, LASS-ICP-MS is superior over LA-MC-ICP-MS|OES, which is limited by its lower sensitivity. Moreover, LASS-ICP-MS offers trace element analysis down to the μg g⁻¹-range for more than 28 elements due to lower limits of detection, and with typical uncertainties better than 15%. For in situ simultaneous stable isotope measurement and chemical composition analysis LASS-ICP-MS in combination with MC-ICP-MS is the method of choice.