Optical microrheology using rotating laser-trapped particles.
نویسندگان
چکیده
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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ورودعنوان ژورنال:
- Physical review letters
دوره 92 19 شماره
صفحات -
تاریخ انتشار 2004