title: Negative-pressure-induced collector for a self-balance free-flow electrophoresis device.
abstract: Uneven flow in free-flow electrophoresis (FFE) with a gravity-induced fraction collector caused by air bubbles in outlets and/or imbalance of the surface tension of collecting tubes would result in a poor separation. To solve these issues, this work describes a novel collector for FFE. The collector is composed of a self-balance unit, multisoft pipe flow controller, fraction collector, and vacuum pump. A negative pressure induced continuous air flow rapidly flowed through the self-balance unit, taking the background electrolyte and samples into the fraction collector. The developed collector has the following advantages: (i) supplying a stable and harmonious hydrodynamic environment in the separation chamber for FFE separation, (ii) effectively preventing background electrolyte and sample flow-back at the outlet of the chamber and improving the resolution, (iii) increasing the preparative scale of the separation, and (iv) simplifying the operation. In addition, the cost of the FFE device was reduced without using a multichannel peristaltic pump for sample collection. Finally, comparative FFE experiments on dyes, proteins, and cells were carried out. It is evident that the new developed collector could overcome the problems inherent in the previous gravity-induced self-balance collector.
authors.affiliation: Laboratory of Analytical Biochemistry and Bioseparation, Key State Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Cheng-Zhang
authors.initials: CZ
authors.lastname: Yang
authors.forename: Jian
authors.initials: J
authors.lastname: Yan
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Chen-Gang
authors.initials: CG
authors.lastname: Guo
authors.forename: Fan-Zhi
authors.initials: FZ
authors.lastname: Kong
authors.forename: Cheng-Xi
authors.initials: CX
authors.lastname: Cao
authors.forename: Liu-Yin
authors.initials: LY
authors.lastname: Fan
authors.forename: Xin-Qiao
authors.initials: XQ
authors.lastname: Jin
mesh_terms: D004396:Coloring Agents / Q000032:analysis; D004586:Electrophoresis / Q000295:instrumentation* / Q000379:methods; D057446:Hydrodynamics; D011312:Pressure; D011506:Proteins / Q000032:analysis
chemical_list: D004396:Coloring Agents; D011506:Proteins
keywords: Flow field; Free-flow electrophoresis; Sample collection