Three-dimensional pore structure of chromatographic adsorbents from electron tomography.
Three-dimensional pore structure of chromatographic adsorbents from electron tomography.
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DOI：
10.1021/la0613225
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发表时间：
2006-11
期刊：
影响因子：
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通讯作者：
Yan Yao;K. Czymmek;R. Pazhianur;A. Lenhoff
中科院分区：
文献类型：
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作者：
Yan Yao;K. Czymmek;R. Pazhianur;A. Lenhoff
色谱吸附剂的孔结构直接影响大分子在色谱中的分配和传递。色谱介质的定量结构表征通常根据平均孔径或至多孔径分布（PSD）进行，但更详细的信息，例如，缺乏连通性。我们应用了电子断层扫描，一种3D TEM技术，从多个角度观察样品，并允许重建体积结构，以纳米级分辨率捕获微孔色谱介质的内部细节。三种吸附剂，Toyopolysis SP-650 C，SP-550 C和CM Sepharose FF的重建的可视化，提供了关于孔网络的几何形状和互连性的全面和直接的信息。的结构是定性一致的原位AFM图像，和定量数据的孔隙度和PSD的断层数据分析同意合理以及与反尺寸排阻色谱的结果。为了更直接地表示无序孔隙空间的网络和尺寸特征，使用3D细化算法来导出孔隙骨架，从而获得关于局部路径长度、宽度、曲折度和连通性分布的定量数据。这种丰富的结构信息可以有助于更有区别的结构评价和工程孔模型的研究溶质颗粒内传输的建设。
The pore structure of chromatographic adsorbents directly influences macromolecular partitioning and transport in chromatography. Quantitative structural characterization of chromatographic media has generally been performed in terms of the mean pore size or, at best, the pore size distribution (PSD), but more detailed information on, e.g., connectivity has been lacking. We have applied electron tomography, a 3D TEM technique that views a sample from multiple perspectives and allows reconstruction of the volumetric structure, to capture the internal details of microporous chromatographic media with nanometer-scale resolution. Visualization of reconstructions of three adsorbents, Toyopearl SP-650 C, SP-550 C, and CM Sepharose FF, provides thorough and direct information on the geometry and the interconnectivity of the pore network. The structures are qualitatively consistent with in situ AFM images, and quantitative data for the porosities and PSDs from the analysis of tomographic data agree reasonably well with inverse size-exclusion chromatography results. For a more straightforward representation of the networking and size features of the disordered pore space, a 3D thinning algorithm was used to derive pore skeletons and consequently quantitative data on distributions of local path lengths, widths, tortuosities, and connectivities. Such enriched structural information can be instrumental in more discriminate structural evaluation and construction of engineered pore models for the study of solute intraparticle transport.