The Optical Stretcher: A Novel Laser Tool to Micromanipulate Cells

Center for Nonlinear Dynamics, Department of Physics, University of Texas at Austin, Texas 78712, USA.
Biophysical Journal (Impact Factor: 3.97). 09/2001; 81(2):767-84. DOI: 10.1016/S0006-3495(01)75740-2
Source: PubMed


When a dielectric object is placed between two opposed, nonfocused laser beams, the total force acting on the object is zero but the surface forces are additive, thus leading to a stretching of the object along the axis of the beams. Using this principle, we have constructed a device, called an optical stretcher, that can be used to measure the viscoelastic properties of dielectric materials, including biologic materials such as cells, with the sensitivity necessary to distinguish even between different individual cytoskeletal phenotypes. We have successfully used the optical stretcher to deform human erythrocytes and mouse fibroblasts. In the optical stretcher, no focusing is required, thus radiation damage is minimized and the surface forces are not limited by the light power. The magnitude of the deforming forces in the optical stretcher thus bridges the gap between optical tweezers and atomic force microscopy for the study of biologic materials.

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    • "Various experimental approaches have been developed that probe different aspects of cellular mechanics. Most of these approaches measure one or a few cells per experiment [7] [8] [9] [10]. The optical stretcher can probe a huge amount of cells in a very short time [11] if cells are in suspension. "
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    • "Briefly, cells were held in between two counter propagating laser beams (λ = 1064 nm). Due to applied laser power, cells experienced both an optical force pulling on the cell membrane (σ ≈ 10Pa peak stress [16]) and an increase in temperature caused by laser light absorption ( "
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    • "During the last few years, different fabrication techniques have been developed (Guck et al. 2001; Lincoln et al. 2007; Bellini et al. 2010), and optical stretchers have been applied to explore the deformability of oral cancer cells (Remmerbach et al. 2009), of Abstract Acoustophoresis is a widely reported and used technique for microparticle manipulation and separation. "
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