A light-induced dielectrophoretic droplet manipulation platform.

We report on a light-actuated, droplet based microfluidic platform enabling two-dimensional (2D) droplet manipulation on an open chamber with a single-side, featureless photoconductive surface. The droplet actuation mechanism is based on recently demonstrated floating electrode optoelectronic tweezers (FEOET), which enable light-induced dielectrophoretic forces to manipulate aqueous droplets immersed in electrically nonconductive oil, with a light intensity as low as 400 microW/cm2. In this paper, we study the shape effect of optical patterns for 2D droplet actuation, and demonstrate light-actuated droplet manipulation functions including 2D droplet transport, merging, mixing, and multidroplet processing, for up to 16 droplets in parallel. Such an open chamber platform also permits easy interfacing and integration with other microfluidic structures, such as wells and close-channel based droplet devices to increase its versatility for biochemical analyses.

[1]  P. Gascoyne,et al.  Droplet-based chemistry on a programmable micro-chip. , 2004, Lab on a chip.

[2]  O. Velev,et al.  Anisotropic particle synthesis in dielectrophoretically controlled microdroplet reactors , 2004, Nature materials.

[3]  Zhiguang Guo,et al.  “Stick and slide” ferrofluidic droplets on superhydrophobic surfaces , 2006 .

[4]  Johan Roeraade,et al.  Continuous segmented-flow polymerase chain reaction for high-throughput miniaturized DNA amplification. , 2003, Analytical chemistry.

[5]  Stephan Herminghaus,et al.  Controlled electrocoalescence in microfluidics: Targeting a single lamella , 2006 .

[6]  Minoru Seki,et al.  Continuous and size-dependent sorting of emulsion droplets using hydrodynamics in pinched microchannels. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[7]  Wei Li,et al.  Multi-step microfluidic polymerization reactions conducted in droplets: the internal trigger approach. , 2008, Journal of the American Chemical Society.

[8]  Rustem F Ismagilov,et al.  A microfluidic approach for screening submicroliter volumes against multiple reagents by using preformed arrays of nanoliter plugs in a three-phase liquid/liquid/gas flow. , 2005, Angewandte Chemie.

[9]  Michael A. Teitell,et al.  Floating electrode optoelectronic tweezers: Light-driven dielectrophoretic droplet manipulation in electrically insulating oil medium. , 2008, Applied physics letters.

[10]  N. Manaresi,et al.  A CMOS chip for individual cell manipulation and detection , 2003, 2003 IEEE International Solid-State Circuits Conference, 2003. Digest of Technical Papers. ISSCC..

[11]  Sigurd Wagner,et al.  Effect of contact angle hysteresis on thermocapillary droplet actuation , 2005 .

[12]  Helen Song,et al.  Controlling nonspecific protein adsorption in a plug-based microfluidic system by controlling interfacial chemistry using fluorous-phase surfactants. , 2005, Analytical chemistry.

[13]  A. Wixforth,et al.  Planar chip device for PCR and hybridization with surface acoustic wave pump. , 2005, Lab on a chip.

[14]  M. Tabrizian,et al.  Water-oil core-shell droplets for electrowetting-based digital microfluidic devices. , 2008, Lab on a chip.

[15]  A. Lee,et al.  Alternating droplet generation and controlled dynamic droplet fusion in microfluidic device for CdS nanoparticle synthesis. , 2006, Lab on a chip.

[16]  Peidong Yang,et al.  Dynamic manipulation and separation of individual semiconducting and metallic nanowires. , 2008, Nature photonics.

[17]  Ming C. Wu,et al.  Massively parallel manipulation of single cells and microparticles using optical images , 2005, Nature.

[18]  Delai L Chen,et al.  Microgram-scale testing of reaction conditions in solution using nanoliter plugs in microfluidics with detection by MALDI-MS. , 2006, Journal of the American Chemical Society.

[19]  A. deMello,et al.  Quantitative detection of protein expression in single cells using droplet microfluidics. , 2007, Chemical communications.

[20]  Rustem F Ismagilov,et al.  Using microfluidics to observe the effect of mixing on nucleation of protein crystals. , 2005, Journal of the American Chemical Society.

[21]  Sung Yong Park,et al.  Continuous optoelectrowetting for picoliter droplet manipulation , 2008 .

[22]  M. Roth,et al.  Digital reaction technology by micro segmented flow—components, concepts and applications , 2004 .

[23]  John A. Crowe,et al.  Direct calculation of Maxwell stress tensor for accurate trajectory prediction during DEP for 2D and 3D structures , 2007 .

[24]  M.C. Wu,et al.  Droplet Manipulation With Light on Optoelectrowetting Device , 2008, Journal of Microelectromechanical Systems.

[25]  Petra Schwille,et al.  A New Embedded Process for Compartmentalized Cell‐Free Protein Expression and On‐line Detection in Microfluidic Devices , 2005, Chembiochem : a European journal of chemical biology.

[26]  Hsan-Yin Hsu,et al.  Optically actuated thermocapillary movement of gas bubbles on an absorbing substrate. , 2007, Applied physics letters.

[27]  Mojtaba Ghadiri,et al.  Drop–drop coalescence in an electric field: the effects of applied electric field and electrode geometry , 2003 .

[28]  R. Westervelt,et al.  Dielectrophoretic manipulation of drops for high-speed microfluidic sorting devices , 2006 .

[29]  Helen Song,et al.  Reactions in droplets in microfluidic channels. , 2006, Angewandte Chemie.

[30]  Peter R. C. Gascoyne,et al.  General expressions for dielectrophoretic force and electrorotational torque derived using the Maxwell stress tensor method , 1997 .

[31]  Chang-Jin C J Kim,et al.  All-electronic droplet generation on-chip with real-time feedback control for EWOD digital microfluidics. , 2008, Lab on a chip.

[32]  C. Rosales,et al.  Numerical comparison between Maxwell stress method and equivalent multipole approach for calculation of the dielectrophoretic force in single‐cell traps , 2005, Electrophoresis.