OSA's Digital Library

Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 51, Iss. 19 — Jul. 1, 2012
  • pp: 4377–4387

Microfluidic sorting with a moving array of optical traps

Raktim Dasgupta, Sunita Ahlawat, and Pradeep Kumar Gupta  »View Author Affiliations

Applied Optics, Vol. 51, Issue 19, pp. 4377-4387 (2012)

View Full Text Article

Enhanced HTML    Acrobat PDF (1308 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



Optical sorting was demonstrated by selective trapping of a set of microspheres (having specific size or composition) from a flowing mixture and guiding these in the desired direction by a moving array of optical traps. The approach exploits the fact that whereas the fluid drag force varies linearly with particle size, the optical gradient force has a more complex dependence on the particle size and also on its optical properties. Therefore, the ratio of these two forces is unique for different types of flowing particles. Selective trapping of a particular type of particles can thus be achieved by ensuring that the ratio between fluid drag and optical gradient force on these is below unity whereas for others it exceeds unity. Thereafter, the trapped particles can be sorted using a motion of the trapping sites towards the output. Because in this method the trapping force seen by the selected fraction of particles can be suitably higher than the fluid drag force, the particles can be captured and sorted from a fast fluid flow (about 150μm/s). Therefore, even when using a dilute particle suspension, where the colloidal trafficking issues are naturally minimized, due to high flow rate a good throughput (about 30particles/s) can be obtained. Experiments were performed to demonstrate sorting between silica spheres of different sizes (2, 3, and 5 μm) and between 3 μm size silica and polystyrene spheres.

© 2012 Optical Society of America

OCIS Codes
(110.0180) Imaging systems : Microscopy
(350.4855) Other areas of optics : Optical tweezers or optical manipulation

ToC Category:
Optical Tweezers or Optical Manipulation

Original Manuscript: February 27, 2012
Revised Manuscript: May 18, 2012
Manuscript Accepted: May 22, 2012
Published: June 26, 2012

Virtual Issues
Vol. 7, Iss. 9 Virtual Journal for Biomedical Optics

Raktim Dasgupta, Sunita Ahlawat, and Pradeep Kumar Gupta, "Microfluidic sorting with a moving array of optical traps," Appl. Opt. 51, 4377-4387 (2012)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. K. Dholakia, M. P. MacDonald, P. Zemanek, and T. Cizmar, “Cellular and colloidal separation using optical forces,” in Methods in Cell Biology, M. Berns and K. Greulich, eds. (Elsevier, 2007), Vol. 82, pp. 467–495.
  2. L. Paterson, E. Papagiakoumou, G. Milne, V. Garcés-Chávez, S. A. Tatarkova, W. Sibbett, F. J. Gunn-Moore, P. E. Bryant, A. C. Riches, and K. Dholakia, “Light-induced cell separation in a tailored optical landscape,” Appl. Phys. Lett. 87, 123901 (2005). [CrossRef]
  3. G. Milne, K. Dholakia, D. McGloin, K. Volke-Sepulveda, and P. Zemánek, “Transverse particle dynamics in a Bessel beam,” Opt. Express 15, 13972–13987 (2007). [CrossRef]
  4. T. Čižmár, M. Šiler, M. Šerý, P. Zemánek, V. Garcés-Chávez, and K. Dholakia, “Optical sorting and detection of submicrometer objects in a motional standing wave,” Phys. Rev. B 74, 035105 (2006). [CrossRef]
  5. P. Jekl, T. Čižmer, M. Šerý, and P. Zemánek, “Static optical sorting in a laser interference field,” Appl. Phys. Lett. 92, 161110 (2008). [CrossRef]
  6. I. Ricárdez-Vargas, P. Rodríguez-Montero, R. Ramos-García, and K. Volke-Sepúlveda, “Modulated optical sieve for sorting of polydisperse microparticles,” Appl. Phys. Lett. 88, 121116 (2006). [CrossRef]
  7. A. S. Zelenina, R. Quidant, G. Badenes, and M. Nieto-Vesperinas, “Tunable optical sorting and manipulation of nanoparticles via plasmon excitation,” Opt. Lett. 31, 2054–2056 (2006). [CrossRef]
  8. A. Terray, J. D. Taylor, and S. J. Hart, “Cascade optical chromatography for sample fractionation,” Biomicrofluidics 3, 044106 (2009). [CrossRef]
  9. K. Ladavac, K. Kasza, and D. G. Grier, “Sorting microscopic objects with periodic potential landscapes: optical fractionation,” Phys. Rev. E 70, 010901 (2004). [CrossRef]
  10. M. P. MacDonald, G. C. Spalding, and K. Dholakia, “Microfluidic sorting in an optical lattice,” Nature 426, 421–424 (2003). [CrossRef]
  11. G. Milne, D. Rhodes, M. MacDonald, and K. Dholakia, “Fractionation of polydisperse colloid with acousto-optically generated potential energy landscapes,” Opt. Lett. 32, 1144–1146 (2007). [CrossRef]
  12. Y. Y. Sun, X.-C. Yuan, L. S. Ong, J. Bu, S. W. Zhu, and R. Liu, “Large-scale optical traps on a chip for optical sorting,” Appl. Phys. Lett. 90, 031107 (2007). [CrossRef]
  13. R. L. Smith, G. C. Spalding, K. Dholakia, and M. P. MacDonald, “Colloidal sorting in dynamic optical lattices,” J. Opt. A 9, S134–S138 (2007). [CrossRef]
  14. K. Xiao and D. G. Grier, “Sorting colloidal particles into multiple channels with optical forces: prismatic optical fractionation,” Phys. Rev. E 82, 051407 (2010). [CrossRef]
  15. M. P. MacDonald, S. Neale, L. Paterson, A. Riches, G. C. Spalding, and K. Dholakia, “Microfluidic optical sorting: particle selection in an optical lattice,” Proc. SPIE 5514, 1–14 (2004). [CrossRef]
  16. J. Happel and H. Brenner, Low Reynolds Number Hydrodynamics (Noordhoff, 1973).
  17. K. F. Ren, G. Gréha, and G. Gouesbet, “Radiation pressure forces exerted on a particle arbitrarily located in a Gaussian beam by using the generalized Lorenz–Mie theory, and associated resonance effects,” Opt. Commun. 108, 343–354 (1994). [CrossRef]
  18. G. Gouesbet, B. Maheu, and G. Gréhan, “Light scattering from a sphere arbitrarily located in a Gaussian beam, using a Bromwich formulation,” J. Opt. Soc. Am. A 5, 1427–1443 (1988). [CrossRef]
  19. Y. K. Nahmias and D. J. Odde, “Analysis of radiation forces in laser trapping and laser-guided direct writing applications,” IEEE J. Quantum Electron. 38, 131–141 (2002). [CrossRef]
  20. E. R. Dufresne, G. C. Spalding, M. T. Dearing, S. A. Sheets, and D. G. Grier, “Computer-generated holographic optical tweezer arrays,” Rev. Sci. Instrum. 72, 1810–1816 (2001). [CrossRef]
  21. J. E. Curtis, B. A. Koss, and D. G. Grier, “Dynamic holographic optical tweezers,” Opt. Commun. 207, 169–175 (2002). [CrossRef]
  22. H. Misawa, M. Koshioka, K. Sasaki, N. Kitamura, and H. Masuhara, “Three-dimensional optical trapping and laser ablation of a single polymer latex particle in water,” J. Appl. Phys. 70, 3829–3835 (1991). [CrossRef]
  23. J. Gelles, B. J. Schnapp, and M. P. Sheetz, “Tracking kinesin-driven movements with nanometre-scale precision,” Nature 331, 450–453 (1988). [CrossRef]
  24. A. L. Givan, Flow Cytometry: First Principles, 2nd ed.(Wiley-Liss, 2001), p. 27.

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited