Study on ICP Mass Spectrometry with Solutions capturing Solid-Sample Particles generated by Laser Ablation

为了提高激光烧蚀(LA)/电感耦合等离子体质谱(ICPMS)定量分析的性能，研究了激光烧蚀(LA)产生的固体样品颗粒在溶液中的利用。在我们的第一种方法中，通过在纯水中将激光脉冲照射到一系列标准钢样品的表面来制备样品溶液。对于标准钢样，样品溶液中被分析物的离子强度与各浓度之间的关系可获得良好的线性关系。然而，与用试剂制备的标准溶液相比，样品和标准溶液的校准曲线斜率有所不同。观察到沸点较高的元素的差异增大，即元素之间的选择性汽化被识别出来。第二种方法是用载气将传统LA系统产生的固体样品颗粒转移到0.1mol/L HN03溶液中。通过绘制样品溶液中分析物的离子强度与标准钢样的每个浓度的关系图，获得了校准曲线。然而，在斜率方面，校准曲线与标准溶液的校准曲线不同，而且绘制的点分散。采用内标法，钴和钼的标准曲线在样品和标准溶液之间重叠。在烧结氮化硅标准样品分析中的应用。准确度和精密度几乎都令人满意。发现了在极短的时间内分析烧结细陶瓷的可能性。

In order to improve the characteristics of quantitative analysis in laser ablation (LA)/ICP-MS, we investigated the utilization of solutions in which solid-sample particles generated by LA were collected. In our first method, sample solutions were prepared by irradiating laser pulses on the surface of a series of standard steel samples in pure water. A good linearity could be obtained when ion intensities of analytes in sample solutions were plotted against each concentration for standard steel samples. Compared to standard solutions prepared from reagents, however, the differences in the slope of calibration curves between sample and standard solutions were found. An increase in the difference was observed for elements with higher boiling points ; i. e., selective vaporization between elements was recognized. By using predetermined factors for compensating the selective vaporization another steel samples could be analyzed only with standard solutions.As a second method, solid-sample particles, which were generated by a conventional LA system, were transferred into 0.1 mol/L HN0_3 solution with carrier gas. Calibration curves were obtained by plotting ion intensities of analytes in sample solutions against each concentration for standard steel samples. The calibration curves, however, differed from those for standard solutions in terms of the slope, and furthermore, the plotted points scattered. By applying an internal standard method, the calibration curves for Co and Mo overlapped between sample and standard solutions. In an application to the analysis for a standard sample of sintered silicon nitride. both accuracy and precision were almost satisfactory. The possibility of analyzing sintered fine-ceramics in an extremely short time was found.