The optical stretcher-A novel laser tool to micromanipulate cells

Author :J. Guck, R. Ananthakrishnan, H. Mahmood, T. J. Moon, C. C. Cunningham, R. Hallworth, and J. Kas
Publication :Biophysical Journal
Volume :81
Pages :767-784
Year :2001

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.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.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.