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Optical microrheology using rotating laser-trapped particles

Alexis I. Bishop·Timo A. Nieminen·Norman R. Heckenberg·Halina Rubinsztein-Dunlop
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Abstract

We demonstrate an optical system that can apply and accurately measure the torque exerted by the trapping beam on a rotating birefringent probe particle. This allows the viscosity and surface effects within liquid media to be measured quantitatively on a micron-size scale using a trapped rotating spherical probe particle. We use the system to measure the viscosity inside a prototype cellular structure.

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Alexis I. Bishop, Timo A. Nieminen, Norman R. Heckenberg, Halina Rubinsztein-Dunlop. 2004-05-17. Optical microrheology using rotating laser-trapped particles. https://doi.org/10.1103/physrevlett.92.198104

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