Mass transfer mechanism in liquid chromatography columns packed with shell particles: would there be an optimum shell structure?
Mass transfer mechanism in liquid chromatography columns packed with shell particles: would there be an optimum shell structure?
复制标题
填充壳颗粒的液相色谱柱的传质机制：是否存在最佳的壳结构？
DOI：
10.1016/j.chroma.2010.10.075
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
G. Guiochon
中科院分区：
文献类型：
--
作者：
F. Gritti;G. Guiochon
从物理化学的角度研究了旧的（55 μ m Zipax和5 μ m Poroshell）和最近商业化的壳颗粒（2.7 μ m Halo-C18和Kinetex-C18）填充柱中的传质机理。结合非均相填充床中的扩散模型（有效介质理论），其高度值相当于理论塔板（HETP来源于洗脱曲线的第一和第二中心矩）和由峰停放方法提供的峰方差，我们证明了填充有当前壳颗粒的柱在分辨低分子量方面比填充有完全多孔颗粒的柱表现更好因为前者的货车Deemter方程的涡动扩散项明显较小。柱床中的涡流扩散的计算表明，较小的A项是由于较小的跨柱速度偏差填充与壳颗粒的列。我们还表明，大分子的传质（例如，当分析物可接近的内部体积增加时，蛋白质）的速度更快。因此，建议由平均孔径随着直径增加而增加的同心层制成的壳颗粒将提供具有更高效率的柱。
The mass transfer mechanisms in columns packed with old (55μm Zipax and 5μm Poroshell) and recently commercialized shell particles (2.7μm Halo-C18and Kinetex-C18) were investigated from a physico-chemical point of view. Combining a model of diffusion in heterogeneous packed beds (effective medium theory) with values of the heights equivalent to a theoretical plate (HETPs derived from the first and second central moments of the elution profiles) and of the peak variances provided by the peak parking method, we demonstrate that columns packed with current shell particles perform better than those packed with fully porous particles in resolving low molecular weight compounds because the eddy diffusion term of the van Deemter equation of the former is markedly smaller. The calculation of eddy diffusion in column beds suggests that the smaller A terms are due to smaller trans-column velocity bias in columns packed with shell particles. We also show that the mass transfer of large molecules (e.g., proteins) is faster when the internal volume accessible to the analyte increases. Therefore, it is suggested that shell particles made of concentric layers with average pore sizes increasing with increasing diameter would provide columns with higher efficiency.
影响因子：
4.1
作者：
Wang, XL;Barber, WE;Carr, PW
通讯作者：
Carr, PW