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

Abstract

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.

© 2006 Optical Society of America

Optimized three-dimensional trapping of aerosols: the effect of immersion medium

S. Mohammad-Reza Taheri, Ebrahim Madadi, Mohammad Sadeghi, and S. Nader S. Reihani
J. Opt. Soc. Am. B 32(7) 1494-1498 (2015)

Polarization-induced stiffness asymmetry of optical tweezers

Ebrahim Madadi, Akbar Samadi, Mojtaba Cheraghian, and S. Nader S. Reihani
Opt. Lett. 37(17) 3519-3521 (2012)

Computational toolbox for optical tweezers in geometrical optics

Agnese Callegari, Mite Mijalkov, A. Burak Gököz, and Giovanni Volpe
J. Opt. Soc. Am. B 32(5) B11-B19 (2015)

Axial optical trapping forces on two particles trapped simultaneously by optical tweezers

Shenghua Xu, Yinmei Li, and Liren Lou
Appl. Opt. 44(13) 2667-2672 (2005)

Direct measurement of axial optical forces

Gregor Thalhammer, Lisa Obmascher, and Monika Ritsch-Marte
Opt. Express 23(5) 6112-6129 (2015)