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Applied Optics

Applied Optics


  • Editor: James C. Wyant
  • Vol. 45, Iss. 16 — Jun. 1, 2006
  • pp: 3885–3892

Optical trapping of a spherically symmetric sphere in the ray-optics regime: a model for optical tweezers upon cells

Yi-Ren Chang, Long Hsu, and Sien Chi  »View Author Affiliations

Applied Optics, Vol. 45, Issue 16, pp. 3885-3892 (2006)

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Since their invention in 1986, optical tweezers have become a popular manipulation and force measurement tool in cellular and molecular biology. However, until recently there has not been a sophisticated model for optical tweezers on trapping cells in the ray-optics regime. We present a model for optical tweezers to calculate the optical force upon a spherically symmetric multilayer sphere representing a common biological cell. A numerical simulation of this model shows that not only is the magnitude of the optical force upon a Chinese hamster ovary cell significantly three times smaller than that upon a polystyrene bead of the same size, but the distribution of the optical force upon a cell is also much different from that upon a uniform particle, and there is a 30% difference in the optical trapping stiffness of these two cases. Furthermore, under a small variant condition for the refractive indices of any adjacent layers of the sphere, this model provides a simple approximation to calculate the optical force and the stiffness of an optical tweezers system.

© 2006 Optical Society of America

OCIS Codes
(080.2720) Geometric optics : Mathematical methods (general)
(140.7010) Lasers and laser optics : Laser trapping
(170.4520) Medical optics and biotechnology : Optical confinement and manipulation

Original Manuscript: April 6, 2005
Revised Manuscript: July 29, 2005
Manuscript Accepted: July 29, 2005

Virtual Issues
Vol. 1, Iss. 7 Virtual Journal for Biomedical Optics

Yi-Ren Chang, Long Hsu, and Sien Chi, "Optical trapping of a spherically symmetric sphere in the ray-optics regime: a model for optical tweezers upon cells," Appl. Opt. 45, 3885-3892 (2006)

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  1. A. Ashkin, J. M. Dziedzic, J. E. Bjorkholm, and S. Chu, "Observation of a single-beam gradient force optical trap for dielectric particles," Opt. Lett. 11, 288-290 (1986). [CrossRef] [PubMed]
  2. S. C. Grover, A. G. Skirtach, R. C. Gauthier, and C. P. Grover, "Automated single-cell sorting system based on optical trapping," J. Biomed. Opt. 6, 14-22 (2001). [CrossRef] [PubMed]
  3. M. Ozkan, T. Pisanic, J. Scheel, C. Barlow, S. Esener, and S. N. Bhatia, "Electro-optical platform for the manipulation of live cells," Langmuir 19, 1532-1538 (2003). [CrossRef]
  4. M. Ozkan, M. Wang, C. Ozkan, R. Flynn, A. Birkbeck, and S. Esener, "Optical manipulation of objects and biological cells in microfluidic devices," Biomed. Microdevices 5, 61-67 (2003). [CrossRef]
  5. Y. Wakamoto, I. Inoue, H. Moriguchi, and K. Yasuda, "Analysis of single-cell differences by use of an on-chip microculture system and optical trapping," Fresenius J. Anal. Chem. 371, 276-281 (2001). [CrossRef] [PubMed]
  6. G. Hummer and A. Szabo, "Free-energy reconstruction from nonequilibrium single-molecule pulling experiments," Proc. Natl. Acad. Sci. U.S.A. 98, 3658-3661 (2001). [CrossRef] [PubMed]
  7. A. Ashkin, "Forces of a single-beam gradient laser trap on a dielectric sphere in the ray optics regime," Biophys. J. 61, 569-582 (1992). [CrossRef] [PubMed]
  8. Y. Harada and T. Asakura, "Radiation forces on a dielectric sphere in the Rayleigh scattering regime," Opt. Commun. 124, 529-541 (1996). [CrossRef]
  9. J. P. Barton, D. R. Alexander, and S. A. Schaub, "Theoretical determination of net radiation force and torque for a spherical particle illuminated by a focused laser beam," J. Appl. Phys. 66, 4594-4602 (1989). [CrossRef]
  10. F. Ren, G. Grehan, and G. Gouesbet, "Radiation pressure forces exerted on a particle located arbitrarily in a Gaussian beam by using the generalized Lorentz-Mie theory, and associated resonance effects," Opt. Commun. 108, 343-354 (1994). [CrossRef]
  11. A. Rohrbach and E. H. K. Stelzer, "Optical trapping of dielectric particles in arbitrary fields," J. Opt. Soc. Am. A 18, 839-153 (2001). [CrossRef]
  12. R. C. Gauthier, "Computation of the optical trapping force using an FDTD based technique," Opt. Express 13, 3707-3718 (2005). [CrossRef] [PubMed]
  13. Y.-R. Chang, L. Hsu, and S. Chi, "Optical trapping of a spherically symmetric Rayleigh sphere: a model for optical tweezers upon cells," Opt. Commun. 246, 97-105 (2005). [CrossRef]
  14. A. Brunsting and P. F. Mullaney, "Differential light scattering from spherical mammalian cells," Biophys. J. 14, 439-453 (1974). [CrossRef] [PubMed]
  15. M. N. Liang, S. P. Smith, S. J. Metallo, I. S. Choi, M. Prentiss, and G. M. Whitesides, "Measuring the forces involved in polyvalent adhesion of uropathogenic Escherichia coli to mannose-presenting surfaces," Proc. Natl. Acad. Sci. U.S.A. 97, 13092-13096 (2000). [CrossRef] [PubMed]

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