title: Optoacoustic tweezers: a programmable, localized cell concentrator based on opto-thermally generated, acoustically activated, surface bubbles.
abstract: 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.
authors.affiliation: Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.|Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Chenglong
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Sixing
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Rufo
authors.affiliation: Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Shikuan
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Feng
authors.initials: F
authors.lastname: Guo
authors.affiliation: Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.|Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Tony Jun
authors.initials: TJ
authors.lastname: Huang
mesh_terms: D000162:Acoustics; D002448:Cell Adhesion; D006367:HeLa Cells; D006801:Humans; D054023:Lasers, Semiconductor; D045423:Microbubbles; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods; D052898:Optical Tweezers