title: On utilizing alternating current-flow field effect transistor for flexibly manipulating particles in microfluidics and nanofluidics.
abstract: By imposing a biased gate voltage to a center metal strip, arbitrary symmetry breaking in induced-charge electroosmotic flow occurs on the surface of this planar gate electrode, a phenomenon termed as AC-flow field effect transistor (AC-FFET). In this work, the potential of AC-FFET with a shiftable flow stagnation line to flexibly manipulate micro-nano particle samples in both a static and continuous flow condition is demonstrated via theoretical analysis and experimental validation. The effect of finite Debye length of induced double-layer and applied field frequency on the manipulating flexibility factor for static condition is investigated, which indicates AC-FFET turns out to be more effective for achieving a position-controllable concentrating of target nanoparticle samples in nanofluidics compared to the previous trial in microfluidics. Besides, a continuous microfluidics-based particle concentrator/director is developed to deal with incoming analytes in dynamic condition, which exploits a design of tandem electrode configuration to consecutively flow focus and divert incoming particle samples to a desired downstream branch channel, as prerequisite for a following biochemical analysis. Our physical demonstrations with AC-FFET prove valuable for innovative designs of flexible electrokinetic frameworks, which can be conveniently integrated with other microfluidic or nanofluidic components into a complete lab-on-chip diagnostic platform due to a simple electrode structure.
authors.affiliation: Micro and Nano-Technology Research Center, State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, People's Republic of China.
authors.forename: Weiyu
authors.initials: W
authors.lastname: Liu
authors.affiliation: Micro and Nano-Technology Research Center, State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, People's Republic of China.
authors.forename: Jinyou
authors.initials: J
authors.lastname: Shao
authors.forename: Yukun
authors.initials: Y
authors.lastname: Ren
authors.affiliation: School of Mechatronics Engineering, Harbin Institute of Technology , West Da-zhi Street 92, Harbin, Heilongjiang 150001, People's Republic of China.
authors.forename: Jiangwei
authors.initials: J
authors.lastname: Liu
authors.affiliation: School of Mechatronics Engineering, Harbin Institute of Technology , West Da-zhi Street 92, Harbin, Heilongjiang 150001, People's Republic of China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Tao
authors.forename: Hongyuan
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Micro and Nano-Technology Research Center, State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, People's Republic of China.
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Ding