Magnetic Tweezers

Applies a precisely calibrated pulling force, and independently a twisting torque, to a single molecule tethered to a magnetic bead, using an external magnetic field with no physical contact.

References

• Bustamante, C., Marko, J.F., Siggia, E.D., Smith, S.B. "Entropic Elasticity." Science 265, no. 5178 (1994): 1599–1600.