Quasi ‘non-destructive’ laser ablation-inductively coupled plasma-mass spectrometry fingerprinting of sapphires
Quasi ‘non-destructive’ laser ablation-inductively coupled plasma-mass spectrometry fingerprinting of sapphires
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蓝宝石的准“非破坏性”激光烧蚀电感耦合等离子体质谱指纹识别
DOI：
10.1016/s0584-8547(01)00185-9
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
D. Günther
中科院分区：
文献类型：
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作者：
M. Guillong;D. Günther
一个均匀的193 nm的准分子激光器与平顶光束轮廓被用来研究LA-ICP-MS的能力，为“准”非破坏性指纹和采购来自不同地点的稀土。蓝宝石中含有97-99%的Al 2 O3（Al 2 O3），其余部分由几种微量元素组成，可以用来区分这些宝石的来源。研究了铝矾土的烧蚀行为，以及确定这些微量元素所需的最小样品去除量。最佳烧蚀条件为6 J cm−2的流率、120 μm的凹坑直径和10 Hz的激光重复频率。烧蚀的最佳时间被确定为2秒，相当于20个激光脉冲。平均样品去除为每脉冲60 nm（约100 nm）。3 ng/脉冲）。这使得令人满意的微量元素测定，并发现造成最小的损害，同时允许指纹的宝石。使用不同的空间分辨率（20-120 μm）测量了40多种同位素，并在来自5个不同地点的25个蓝宝石样品中重复检测了8种元素。微量元素分布的再现性受到样品不均匀性的限制。使用每份样品5次或5次以上重复分析的平均值。使用NIST 612玻璃参考物质作为外标进行校准。ICP-MS的线性动态范围（九个数量级）允许使用Al（蓝宝石中的主要元素）作为内标。大多数轻元素的检测极限在μg g− 1范围内，而较重元素（质量>85）的检测极限更好，在0.1 μg g− 1范围内。通过与同一组样品的XRF分析进行比较，证明了测定的准确性。利用LA-ICP-MS定量分析，采用三元图和主成分分析对5种不同来源的天然红柱石进行了统计分类。
A homogenized 193 nm excimer laser with a flat-top beam profile was used to study the capabilities of LA-ICP-MS for ‘quasi’ non-destructive fingerprinting and sourcing of sapphires from different locations. Sapphires contain 97–99% of Al2O3(corundum), with the remainder composed of several trace elements, which can be used to distinguish the origin of these gemstones. The ablation behavior of sapphires, as well as the minimum quantity of sample removal that is required to determine these trace elements, was investigated. The optimum ablation conditions were a fluency of 6 J cm−2, a crater diameter of 120 μm, and a laser repetition rate of 10 Hz. The optimum time for the ablation was determined to be 2 s, equivalent to 20 laser pulses. The mean sample removal was 60 nm per pulse (approx. 3 ng per pulse). This allowed satisfactory trace element determination, and was found to cause the minimum amount of damage, while allowing for the fingerprinting of sapphires. More than 40 isotopes were measured using different spatial resolutions (20–120 μm) and eight elements were reproducibly detected in 25 sapphire samples from five different locations. The reproducibility of the trace element distribution is limited by the heterogeneity of the sample. The mean of five or more replicate analyses per sample was used. Calibration was carried out using NIST 612 glass reference material as external standard. The linear dynamic range of the ICP-MS (nine orders of magnitude) allowed the use of Al, the major element in sapphire, as an internal standard. The limits of detection for most of the light elements were in the μg g−1range and were better for heavier elements (mass >85), being in the 0.1 μg g−1range. The accuracy of the determinations was demonstrated by comparison with XRF analyses of the same set of samples. Using the quantitative analyses obtained using LA-ICP-MS, natural sapphires from five different origins were statistically classified using ternary plots and principal multi-component analysis.