ANYL 286 |
| The Hollow Fiber Flow Field-Flow Fractionation (HF FlFFF) is a miniaturized technique which allows for the fractionation of nano- and micro-sized particles. The Hollow fiber channel used is a prototype realized in our laboratory and incorporates a tubular Polysulfone porous membrane of 200µm ID (Spectra/Por® in vivo Microdialysis Hollow Fibers, Spectrum Laboratories, Inc. Rancho Dominguez, CA) into a chromatographic-like system. The retention of the sample in the micro channel is due the combined action of an eluent flow and a hydrodynamic field, generated from the eluent flow itself, by the porosity of the channel walls. The mechanism of the separation is ideally purely physical and does not involve the chemical properties of mobile phase. It is hence possible to choose a mobile phase according to the nature of the sample. It is possible, for instance, to use a phosphate buffer or even the culture media to analyze cells. Differences in hydrodynamic diameter, rigidity, and shape between the sample components determine different retention in the channel, hence fractionation. This is an extremely gentle separation mechanism, particularly well suited to bio-samples, since it preserves sample viability and there is no need for labeling or any other pretreatment. The channel is disposable, so cross contamination issues are eliminated. The HF FlFFF has already been shown to be capable of fractionating cells. Our development of the separative apparatus, and analysis procedure, allows for use with human hematopoietic progenitor cells. We choose KG1a cells as a model sample for progenitor cells. KG1a is a primitive human hematopoietic cell line of myeloid progenitor cells, characterized by high expression of the CD34 surface antigen. The results obtained with this progenitor line are the subject of this presentation.
|
|
Analytical Approaches: Separation Science
1:30 PM-5:00 PM, Wednesday, 13 September 2006 Moscone Center -- Room 130, Oral
Division of Analytical Chemistry |