Optoacoustic tweezers: a programmable, localized cell concentrator based on opto-thermally generated, acoustically activated, surface bubbles.

We present a programmable, biocompatible technique for dynamically concentrating and patterning particles and cells in a microfluidic device. Since our technique utilizes opto-thermally generated, acoustically activated, surface bubbles, we name it "optoacoustic tweezers". The optoacoustic tweezers are capable of concentrating particles/cells at any prescribed locations in a microfluidic chamber without the use of permanent structures, rendering it particularly useful for the formation of flexible, complex cell patterns. Additionally, this technique has demonstrated excellent biocompatibility and can be conveniently integrated with other microfluidic units. In our experiments, micro-bubbles were generated by focusing a 405 nm diode laser onto a gold-coated glass chamber. By properly tuning the laser, we demonstrate precise control over the position and size of the generated bubbles. Acoustic waves were then applied to activate the surface bubbles, causing them to oscillate at an optimized frequency. The resulting acoustic radiation force allowed us to locally trap particles/cells, including 15 μm polystyrene beads and HeLa cells, around each bubble. Cell-adhesion tests were also conducted after cell concentrating to confirm the biocompatibility of this technique.

[1]  Sung Jae Kim,et al.  Continuous-flow biomolecule and cell concentrator by ion concentration polarization. , 2011, Analytical chemistry.

[2]  Yi Zhang,et al.  Continuous dielectrophoretic bacterial separation and concentration from physiological media of high conductivity. , 2011, Lab on a chip.

[3]  Andreas Manz,et al.  Latest developments in micro total analysis systems. , 2010, Analytical chemistry.

[4]  M. Lipson,et al.  Optofluidic trapping and transport on solid core waveguides within a microfluidic device. , 2007, Optics express.

[5]  Daniel Ahmed,et al.  A millisecond micromixer via single-bubble-based acoustic streaming. , 2009, Lab on a chip.

[6]  Adrian Neild,et al.  Selective particle trapping using an oscillating microbubble. , 2011, Lab on a chip.

[7]  Sascha Hilgenfeldt,et al.  Efficient manipulation of microparticles in bubble streaming flows. , 2012, Biomicrofluidics.

[8]  I-Kao Chiang,et al.  On-chip manipulation of single microparticles, cells, and organisms using surface acoustic waves , 2012, Proceedings of the National Academy of Sciences.

[9]  S. Mitragotri,et al.  Ultrasound-mediated transdermal protein delivery , 1995, Science.

[10]  Carsten Hermann,et al.  Microfluidic concentration of bacteria by on-chip electrophoresis. , 2011, Biomicrofluidics.

[11]  Xiaoqiang Hong,et al.  Microfabricated ratchet structure integrated concentrator arrays for synthetic bacterial cell-to-cell communication assays. , 2012, Lab on a chip.

[12]  Daniel Ahmed,et al.  Tunable, pulsatile chemical gradient generation via acoustically driven oscillating bubbles. , 2013, Lab on a chip.

[13]  Daniel Ahmed,et al.  Focusing microparticles in a microfluidic channel with standing surface acoustic waves (SSAW). , 2008, Lab on a chip.

[14]  T. Huang,et al.  Continuous particle separation in a microfluidic channel via standing surface acoustic waves (SSAW). , 2009, Lab on a chip.

[15]  M. Yamada,et al.  Hydrodynamic filtration for on-chip particle concentration and classification utilizing microfluidics. , 2005, Lab on a chip.

[16]  Lin Wang,et al.  Standing surface acoustic wave (SSAW) based multichannel cell sorting. , 2012, Lab on a chip.

[17]  Sung Kwon Cho,et al.  Concentration and binary separation of micro particles for droplet-based digital microfluidics. , 2007, Lab on a chip.

[18]  Pak Kin Wong,et al.  Electrokinetic focusing and separation of mammalian cells in conductive biological fluids. , 2012, The Analyst.

[19]  F. S. Foster,et al.  Ultrasound backscatter microscopy images the internal structure of living tumour spheroids , 1987, Nature.

[20]  Steven L Neale,et al.  Phototransistor-based optoelectronic tweezers for dynamic cell manipulation in cell culture media. , 2010, Lab on a chip.

[21]  Caitlin Smith,et al.  Tools for drug discovery: Tools of the trade , 2007, Nature.

[22]  Fook Siong Chau,et al.  Filter-based microfluidic device as a platform for immunofluorescent assay of microbial cells. , 2004, Lab on a chip.

[23]  A. Manz,et al.  Revisiting lab-on-a-chip technology for drug discovery , 2012, Nature Reviews Drug Discovery.

[24]  Jinjie Shi,et al.  Tunable patterning of microparticles and cells using standing surface acoustic waves. , 2012, Lab on a chip.

[25]  Sascha Hilgenfeldt,et al.  Size-sensitive sorting of microparticles through control of flow geometry , 2011 .

[26]  W. Nyborg.  Acoustic Streaming near a Boundary , 1958 .

[27]  Chih-Ming Ho,et al.  Electrokinetic bioprocessor for concentrating cells and molecules. , 2004, Analytical chemistry.

[28]  Shi-ning Zhu,et al.  Accumulating microparticles and direct-writing micropatterns using a continuous-wave laser-induced vapor bubble. , 2011, Lab on a chip.

[29]  Tandiono Tandiono,et al.  Sonolysis of Escherichia coli and Pichia pastoris in microfluidics. , 2012, Lab on a chip.

[30]  R. Bashir,et al.  How far cardiac cells can see each other mechanically , 2011 .

[31]  Hyundoo Hwang,et al.  Rapid and selective concentration of microparticles in an optoelectrofluidic platform. , 2009, Lab on a chip.

[32]  S. Bhatia,et al.  An extracellular matrix microarray for probing cellular differentiation , 2005, Nature Methods.

[33]  Leslie Y Yeo,et al.  Microparticle collection and concentration via a miniature surface acoustic wave device. , 2007, Lab on a chip.

[34]  Chao Liu,et al.  Double spiral microchannel for label-free tumor cell separation and enrichment. , 2012, Lab on a chip.

[35]  S. Pillai,et al.  A microfluidic device for continuous capture and concentration of microorganisms from potable water. , 2007, Lab on a chip.

[36]  Hyundoo Hwang,et al.  Optoelectrofluidic control of colloidal assembly in an optically induced electric field. , 2009, Langmuir : the ACS journal of surfaces and colloids.

[37]  Yuliang Xie,et al.  Single-shot characterization of enzymatic reaction constants Km and kcat by an acoustic-driven, bubble-based fast micromixer. , 2012, Analytical chemistry.

[38]  Maulik V. Patel,et al.  Lateral cavity acoustic transducer as an on-chip cell/particle microfluidic switch. , 2012, Lab on a chip.

[39]  I-Kao Chiang,et al.  Three-dimensional continuous particle focusing in a microfluidic channel via standing surface acoustic waves (SSAW). , 2011, Lab on a chip.

[40]  Kai Zhang,et al.  Laser-induced thermal bubbles for microfluidic applications. , 2011, Lab on a chip.

[41]  Mehmet Toner,et al.  Cell handling using microstructured membranes. , 2006, Lab on a chip.

[42]  Ting-Hsiang Wu,et al.  High-speed droplet generation on demand driven by pulse laser-induced cavitation. , 2011, Lab on a chip.

[43]  D. Sinton,et al.  Radial sample preconcentration. , 2011, Lab on a chip.

[44]  Kam W Leong,et al.  Microfluidic synthesis of multifunctional Janus particles for biomedical applications. , 2012, Lab on a chip.

[45]  Daniel Ahmed,et al.  Acoustic tweezers: patterning cells and microparticles using standing surface acoustic waves (SSAW). , 2009, Lab on a chip.

[46]  Tony Jun Huang,et al.  Milliseconds microfluidic chaotic bubble mixer , 2009 .

[47]  T. Leighton.  The Acoustic Bubble , 1994 .

[48]  Rashid Bashir,et al.  A multifunctional micro-fluidic system for dielectrophoretic concentration coupled with immuno-capture of low numbers of Listeria monocytogenes. , 2006, Lab on a chip.

[49]  Dino Di Carlo,et al.  Automated cellular sample preparation using a Centrifuge-on-a-Chip. , 2011, Lab on a chip.

[50]  Andrea Prosperetti,et al.  Bubble phenomena in sound fields: part one , 1984 .

[51]  Thomas Laurell,et al.  Non-contact acoustic cell trapping in disposable glass capillaries. , 2010, Lab on a chip.

[52]  P. Yager,et al.  Continuous concentration of bacteria in a microfluidic flow cell using electrokinetic techniques , 2001, Electrophoresis.

[53]  D. Sinton,et al.  Optofluidic concentration: plasmonic nanostructure as concentrator and sensor. , 2012, Nano letters.

[54]  Tony Jun Huang,et al.  Microfluidic diagnostics for the developing world. , 2012, Lab on a chip.

[55]  Rashid Bashir,et al.  Patterned Three‐Dimensional Encapsulation of Embryonic Stem Cells using Dielectrophoresis and Stereolithography , 2013, Advanced healthcare materials.

[56]  H. Rubin,et al.  Density Dependent Inhibition of Cell Growth in Culture , 1967, Nature.

[57]  Seongyong Park,et al.  A microfluidic concentrator array for quantitative predation assays of predatory microbes. , 2011, Lab on a chip.

[58]  D. Miller,et al.  Particle gathering and microstreaming near ultrasonically activated gas-filled micropores. , 1988, The Journal of the Acoustical Society of America.

[59]  Robert Langer,et al.  Direct patterning of mammalian cells onto porous tissue engineering substrates using agarose stamps. , 2005, Biomaterials.

[60]  David Erickson,et al.  Directed self-assembly of microcomponents enabled by laser-activated bubble latching. , 2011, Langmuir : the ACS journal of surfaces and colloids.

[61]  Tony Jun Huang,et al.  Surface acoustic wave (SAW) acoustophoresis: now and beyond. , 2012, Lab on a chip.

[62]  Daniel Ahmed,et al.  A fast microfluidic mixer based on acoustically driven sidewall-trapped microbubbles , 2009 .