Investigation of the atomization mechanism of gold nanoparticles in graphite furnace atomic absorption spectrometry
Investigation of the atomization mechanism of gold nanoparticles in graphite furnace atomic absorption spectrometry
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石墨炉原子吸收光谱法中金纳米粒子原子化机理的研究
DOI：
10.1016/j.sab.2018.10.004
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发表时间：
2018-12-01
影响因子：
3.3
通讯作者：
Leopold, Kerstin
中科院分区：
文献类型：
--
作者：
Brandt, Anja;Leopold, Kerstin
最近，石墨炉原子吸收光谱法（GFAAS）已被引入作为一种新的工具来区分银离子和纳米颗粒使用石墨炉原子吸收光谱法（GFAAS）通过评估新提出的参数原子化延迟（t（ad））和原子化速率（k（at））。此外，几位作者显示了通过GFAAS测量的水性悬浮液中NP的尺寸。然而，NPs在GFAAS中的原子化机理以及与引入石墨炉中的离子盐的可能差异尚未被研究。因此，在这项工作中，我们研究了新引入的参数和进一步的峰特性，如半峰全宽（FWHM），峰不对称性和出现时间（t（Ap））和它们的浓度依赖性趋势应用离子金Au（III）标准品以及5- 100 nm大小的金纳米粒子（AuNPs），分别。数据的解释有助于启发的原子释放过程的原子化机制和动力学的AuNPs相比，离子Au（III）。离子型Au（III）的t（ad）随着金浓度的增加而呈上升趋势，而AuNP在此浓度范围内的t（ad）几乎是恒定的。另一方面，离子Au（III）的AAS峰显示常数t（Ap），而AuNP显示出现时间的偏移。此外，与AuNP相比，离子型Au（III）的峰不对称性不同。这些差异表明，不同的原子化机制参与的金原子的蒸发引入到石墨炉作为离子Au（III）的解决方案或AuNP水溶胶。
Recently, graphite furnace atomic absorption spectrometry (GFAAS) has been introduced as a new tool to distinguish between silver ions and nanoparticles using graphite furnace atomic absorption spectrometry (GFAAS) by evaluation of the newly presented parameters atomization delay (t(ad)) and atomization rate (k(at)). Moreover, sizing of NPs in aqueous suspensions by GFAAS measurement was shown by several authors. However, the atomization mechanism of NPs in GFAAS and possible differences to ionic salts introduced into the graphite furnace has not yet been investigated. In this work, therefore we study the newly introduced parameters and further peak characteristics, like full width at half maximum (FWHM), peak asymmetry and appearance time (t(Ap)) and their concentration-dependent trends applying ionic gold Au(III) standards as well as 5- to 100-nm-sized gold nanoparticles (AuNPs), respectively. Interpretation of the data helps to enlighten the atomization mechanism and kinetic of the atom release process of AuNPs in comparison to ionic Au(III). Ionic Au(III) shows a rising trend in t(ad) with increasing gold concentrations, whereas t(ad) is nearly constant for AuNPs over this concentration range. On the other hand, AAS peaks of ionic Au(III) reveal constant t(Ap), while AuNPs show a shift in appearance time. Moreover, peak asymmetry differs for ionic Au(III) in comparison to AuNPs. These differences suggest different atomization mechanisms involved in the evaporation of gold atoms introduced into the graphite furnace as either ionic Au(III) solution or AuNP hydrosol.