title: Numerical simulation of electrokinetic injection techniques in capillary electrophoresis microchips.
abstract: The effective design and control of a capillary electrophoresis (CE) microchip requires a thorough understanding of the electrokinetic transport phenomena associated with its microfluidic injection system. The present study utilizes a numerical simulation approach to investigate these electrokinetic transport processes and to study the control parameters of the injection process. Injection systems with a variety of different configurations are designed and tested, including the cross-form, T-form, double-T-form, variable-volume focused flow cross-form, and variable-volume triple-T-form configuration. Each injection system cycles through a predetermined series of steps in which the magnitudes and distributions of the applied electric field are precisely manipulated in order to effectuate a virtual valve. This study investigates the sample leakage effect associated with each of the injection configurations and applies the double-L, pullback, and focusing injection techniques to minimize the sample leakage effect. The injection methods presented in this paper have the exciting potential for use in high-quality, high-throughput chemical analysis applications and throughout the micro-total-analysis systems field.
authors.affiliation: Department of Vehicle Engineering, National Pingtung University of Science and Technology, Pingtung, Taiwan.
authors.forename: Chien-Hsiung
authors.initials: CH
authors.lastname: Tsai
authors.forename: Ruey-Jen
authors.initials: RJ
authors.lastname: Yang
authors.forename: Chang-Hsien
authors.initials: CH
authors.lastname: Tai
authors.forename: Lung-Ming
authors.initials: LM
authors.lastname: Fu
mesh_terms: D046209:Electrophoresis, Microchip; D007267:Injections / Q000379:methods; D007700:Kinetics; D008433:Mathematics; D008962:Models, Theoretical