We present a simple experimental setup of magneto-optical tweezers built around an inverted microscope. Two pairs of coils placed around the focal point of the objective generate a planar-rotating magnetic field that is perpendicular to the stretching direction. This configuration allows us to control the rotary movement of a paramagnetic bead trapped in the optical tweezers. The mechanical design is universal and can be simply adapted to any inverted microscope and objective. The mechanical configuration permits the use of a rather large experimental cell and the simple assembly and disassembly of the magnetic attachment.
© 2005 Optical Society of America
(140.7010) Lasers and laser optics : Laser trapping
(170.0180) Medical optics and biotechnology : Microscopy
(170.1420) Medical optics and biotechnology : Biology
(230.3810) Optical devices : Magneto-optic systems
Cyril Claudet and Jan Bednar, "Magneto-optical tweezers built around an inverted microscope," Appl. Opt. 44, 3454-3457 (2005)