skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

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

Journal Article · · Applied Optics
DOI:https://doi.org/10.1364/AO.45.0· OSTI ID:20779349

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.

OSTI ID:
20779349
Journal Information:
Applied Optics, Vol. 45, Issue 16; Other Information: DOI: 10.1364/AO.45.003885; (c) 2006 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6935
Country of Publication:
United States
Language:
English