title: Cell separation by the combination of microfluidics and optical trapping force on a microchip.
abstract: We investigated properties of cells affecting their optical trapping force and successfully established a novel cell separation method based on the combined use of optical trapping force and microfluidics on a microchip. Our investigations reveal that the morphology, size, light absorption, and refractive index of cells are important factors affecting their optical trapping force. A sheath flow of sample solutions created in a microchip made sample cells flow in a narrow linear stream and an optical trap created by a highly focused laser beam captured only target cells and altered their trajectory, resulting in high-efficiency cell separation. An optimum balance between optical trapping force and sample flow rate was essential to achieve high cell separation efficiency. Our investigations clearly indicate that the on-chip optical trapping method allows high-efficiency cell separation without cumbersome and time-consuming cell pretreatments. In addition, our on-chip optical trapping method requires small amounts of sample and may permit high-throughput cell separation and integration of other functions on microchips.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Nagoya, 464-8603, Japan.
authors.forename: Masaya
authors.initials: M
authors.lastname: Murata
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Okamoto
authors.forename: Yeon-Su
authors.initials: YS
authors.lastname: Park
authors.forename: Noritada
authors.initials: N
authors.lastname: Kaji
authors.forename: Manabu
authors.initials: M
authors.lastname: Tokeshi
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Baba
mesh_terms: D002469:Cell Separation / Q000379:methods*; D006367:HeLa Cells; D006801:Humans; D046208:Microchip Analytical Procedures / Q000379:methods*; D044085:Microfluidics / Q000379:methods*; D055095:Optics and Photonics / Q000379:methods*; D015203:Reproducibility of Results