Potgieter-Vermaak S S, Van Grieken R
Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium.
Appl Spectrosc. 2006 Jan;60(1):39-47. doi: 10.1366/000370206775382848.
Raman spectrometry has been used to determine the graphitic C content and to estimate particle size and disordered character of the C in aerosol particulate matter collected on filters, with sample spot sizes on the order of 100 microm being analyzed. Individual analysis of particulate matter with aerodynamic diameters less than 10 microm has therefore not been considered. In this investigation, various size fractions of aerosol particulate matter originating from both indoor and outdoor sources were collected by means of impactors or passive dry deposition on different types of substrate and analyzed by means of micro-Raman spectrometry with spot sizes ranging from 1-5 microm. The aim was to investigate the possible application of micro-Raman spectrometry to the molecular characterization of individual aerosol particles and to assess the applicability of the various substrates in such an analysis. It was demonstrated that the molecular characterization of most inorganic particles is trivial, but organic and heterogeneous conglomerates proved to be more challenging. Spectral contributions of the substrates, currently favored for individual particle analysis, were significant. Results obtained from micro Raman spectrometry can certainly add valuable molecular information on individual aerosol particles as small as 1 microm aerodynamic diameter.
拉曼光谱法已被用于测定滤膜上收集的气溶胶颗粒物中石墨碳的含量，并估算其中碳的粒径和无序特征，分析的样品斑点尺寸约为100微米。因此，尚未考虑对空气动力学直径小于10微米的颗粒物进行单独分析。在本研究中，通过撞击器或被动干沉积法，在不同类型的基质上收集了来自室内和室外源的各种粒径级别的气溶胶颗粒物，并采用光斑尺寸为1 - 5微米的显微拉曼光谱法进行分析。目的是研究显微拉曼光谱法在单个气溶胶颗粒分子表征方面的可能应用，并评估各种基质在这种分析中的适用性。结果表明，大多数无机颗粒的分子表征较为简单，但有机颗粒和异质聚集体的表征更具挑战性。目前有利于单个颗粒分析的基质的光谱贡献显著。显微拉曼光谱法获得的结果肯定能为空气动力学直径小至1微米的单个气溶胶颗粒增添有价值的分子信息。
