Edwards Thayne L, Gale Bruce K, Frazier A Bruno
Department of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta 30332, USA.
Anal Chem. 2002 Mar 15;74(6):1211-6. doi: 10.1021/ac010653d.
A microscale thermal field-flow fractionation (micro-TFFF) system has been designed, fabricated, and characterized. Motivation for miniaturization of TFFF systems was established by examining the geometrical scaling of the fundamental TFFF theory. Miniaturization of conventional macroscale TFFF systems was made possible through utilization of micromachining technologies. Fabrication of the micro-TFFF system was discussed in detail. The micro-TFFF system was characterized for plate height versus flow rate, single-component polystyrene retention, and multicomponent polystyrene separations. Retention, thermal diffusion coefficients, and maximum diameter-based selectivity values were extracted from separation data and found comparable with macroscale TFFF system results. Retention values ranged from 0.33 to 0.46. Thermal diffusion coefficients were between 3.0 x 10(-8) and 5.4 x 10(-8) cm2/s x K. The maximum diameter-based selectivity was 1.40.
设计、制造并表征了一种微尺度热场流分级（micro-TFFF）系统。通过研究基本TFFF理论的几何尺度关系，确立了TFFF系统小型化的动机。利用微加工技术实现了传统宏观尺度TFFF系统的小型化。详细讨论了微-TFFF系统的制造过程。对微-TFFF系统进行了表征，考察了板高与流速的关系、单组分聚苯乙烯的保留情况以及多组分聚苯乙烯的分离情况。从分离数据中提取了保留值、热扩散系数和基于最大直径的选择性值，发现这些值与宏观尺度TFFF系统的结果相当。保留值范围为0.33至0.46。热扩散系数在3.0×10⁻⁸至5.4×10⁻⁸ cm²/s·K之间。基于最大直径的选择性为1.40。
