Bio-manipulation and Bio-marking by Optically-Induced Electrokinetics

Optically-induced dielectrophoresis (ODEP)-based bio-manipulation is a new paradigm for cell manipulation as it offers most of the capabilities of laser-based tweezers, but with at least a 10 times reduction in system cost. It also allows for parallel manipulation of hundreds of cells with micron-scale diameters, a capability that is extremely difficult to accomplish with laser-based tweezers. In addition, ODEP systems have also been demonstrated for separating and assembling nano-scale particles and bioentities with high-throughput, a feat that is unmatchable by laser-based manipulation strategy. Our research groups at the City University of Hong Kong (CityU) and the Shenyang Institute of Automation (SIA), Chinese Academy of Sciences, have recently built the first integrated ODEP platforms in Hong Kong and China, respectively, and have demonstrated massive and parallel micro-/nano-scale manipulation, separation, and assembly using these systems. Moreover, in collaboration with other medical science research teams, we have recently discovered that self-induced rotational motion of pigmented biological cells (Le., melan-a cells) in a dielectrophoretic (DEP) force field is possible - a potential application for this discovery is to use the self-induced rotation phenomenon as a bio-marker to separate pigmented and non-pigmented cells. In this project, we propose to explore the possibility of using automation and digitally generated DEP forces to dynamically trap and manipulate moving cells, and then use specific ODEP force fields to induce rotation on various pigmented cells - with the ultimate goal of experimentally and theoretically investigate DEP-induced rotation as a bio-marking mechanism. In order to accomplish this objective, our research teams in Hong Kong and China will collaborate to explore the fundamental phenomena related to using optically-induced electrokinetics (Le., forces related to dielectrophoresis, AC electro-osmosis, electrothermal effect, etc.) to manipulate and assembly nano-/bio-entities, with a near-term goal of establishing the Joint Laboratory for Rio and Nano Electrokinetics between CityU and SIA, which will be one of the first laboratories in the world dedicated to this new and exciting field of optically-induced electrokinetics-based nano/bio manipulation, separation, assembly, and identification.