We demonstrate passive optical sorting of cell populations in the absence of any externally driven fluid flow. Specifically, we report the movement of erythrocytes and lymphocytes in an optical landscape, consisting of a circularly symmetric light pattern created by a Bessel light beam. These distinct cell populations move, spontaneously and differentially, across the underlying periodic optical landscape. Thus, we were able to separate lymphocytes from a mixed population of cells containing erythrocytes and then collect the lymphocytes in a microcapillary reservoir. We also demonstrate an enhanced form of this separation that exploits the polarizability of silica microspheres by attaching spheres coated with antibodies to cell surface markers to a subpopulation of lymphocytes. These techniques may be applied using standard laboratory apparatus.
Bibliographical noteFunding Information:
The authors thank G. Spalding, D. McGloin, E. Brown, C. Briscoe, M.L. McRobbie, and M. Comrie for useful discussions. This work is funded by the Scottish Higher Education Funding Council, the Medical Research Council, and the European Science Foundation EUROCORES Programme SONS , project NOMSAN, supported by funds from the UK Engineering and Physical Sciences Programme and the EC Sixth Framework Programme. One of the authors (E.P.) acknowledges support from the “Heraclitus” project, cofunded by the European Social Fund (75%) and National Resources (25%).
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)