Analytical silica monoliths with submicron macropores: current limitations to a direct morphology-column efficiency scaling.
Analytical silica monoliths with submicron macropores: current limitations to a direct morphology-column efficiency scaling.
复制标题
具有亚微米大孔的分析二氧化硅整体：直接形态柱有效缩放的当前限制
DOI：
10.1016/j.chroma.2013.08.087
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
U. Tallarek
中科院分区：
文献类型：
--
作者：
K. Hormann;U. Tallarek
收缩微粒床或整料的结构元件（即，颗粒或区域尺寸）仅在该过程中保持床的均匀性时才产生更有效的柱。我们调查了这个复杂的问题，一组第二代分析二氧化硅整料与大孔达到亚微米尺寸，使用色谱法，压汞孔隙率法，扫描电子显微镜，共聚焦激光扫描显微镜（CLSM），并提出涡流色散模拟和弦长分布分析的CLSM为基础的物理重建在大孔分辨率。综合结果使我们能够确定从第一代到第二代整体式的相关形态学进步，并进一步强调了目前直接形态学效率缩放的局限性，这些色谱柱可以在HPLC实践中实现。尽管从第一代到第二代二氧化硅整料的径向均匀性的改善由柱效率的显著增加表示，但是第二代整料中大孔尺寸的进一步减小不会导致板高度数据的预期改善，尽管这些整料在同时保持的大孔空间均匀性和可忽略的径向不均匀性下实现了亚微米大孔。我们的研究表明，进一步提高柱效的限制来自所用4.6 mm内径的固有边界效应。分析柱。这包括样品分布到整料上，以及分别通过色谱柱入口和出口处的端部接头进行异步样品收集。只有当这些影响减少时，额外改进的第二代整料才能达到柱效率，这是基于它们的形态学特性为它们设想的。
Shrinking the structural elements of a particulate bed or monolith (i.e., the particle or domain size) yields more efficient columns only when the homogeneity of the bed can be conserved in that process. We investigate this complex issue for a set of 2nd generation analytical silica monoliths with macropores reaching submicron dimensions using chromatographic methods, mercury intrusion porosimetry, scanning electron microscopy, and confocal laser scanning microscopy (CLSM), and present eddy dispersion simulations and a chord length distribution analysis for the CLSM-based physical reconstructions at macropore resolution. The combined results allow us to identify relevant morphological advances made from 1st to 2nd generation monoliths and additionally highlight the current limitations to a direct morphology–efficiency scaling with respect to the performance that can be accomplished in HPLC practice with these columns. Whereas the improvement in radial homogeneity from 1st to 2nd generation silica monoliths is represented by a dramatic increase in column efficiency, the further reduction of macropore size in the 2nd generation monoliths does not lead to the expected improvement of plate height data, although these monoliths realize submicron macropores at a simultaneously conserved bulk macropore space homogeneity and negligible radial heterogeneity. Our study implies that limitations to further improved column efficiency arise from the intrinsic border effects of the used 4.6 mm i.d. analytical columns. This includes the sample distribution onto the monoliths and asynchronous sample collection through the endfittings at the column inlet and outlet, respectively. Only when these effects are reduced will additionally improved 2nd generation monoliths live up to column efficiencies, which are envisioned for them based on their morphological properties.
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超高压液相色谱中填充 1.7 微米颗粒的窄孔柱的传质阻力。
影响因子：
4.1
作者：
F. Gritti;G. Guiochon
通讯作者：
G. Guiochon
DOI：
10.1146/annurev.anchem.1.031207.113014
发表时间：
2010-01-01
期刊：
ANNUAL REVIEW OF ANALYTICAL CHEMISTRY, VOL 3
影响因子：
--
作者：
Jorgenson, James W.
通讯作者：
Jorgenson, James W.
硅胶整体式 HPLC 柱的结构和性能。
影响因子：
3.1
作者：
S. Altmaier;K. Cabrera
通讯作者：
K. Cabrera
影响因子：
4.1
作者：
Kele, M;Guiochon, G
通讯作者：
Guiochon, G
DOI：
--
发表时间：
2009
期刊：
Physical review. E, Statistical, nonlinear, and soft matter physics
影响因子：
--
作者：
Iwan Schenker;F. Filser;L. Gauckler;T. Aste;H. Herrmann
通讯作者：
H. Herrmann