laboratoire de physique statistique
 
 
laboratoire de physique statistique

Publications

Rechercher
2011 


Jean-François ALLEMAND 


1
P U B L I C A T I O N S



 
2011
Soft magnetic tweezers: A proof of principle - Mosconi, Francesco and Allemand, Jean Francois and Croquette, Vincent
REVIEW OF SCIENTIFIC INSTRUMENTS 82 (2011) 
LPS


Abstract : We present here the principle of soft magnetic tweezers which improve the traditional magnetic tweezers allowing the simultaneous application and measurement of an arbitrary torque to a deoxyribonucleic acid (DNA) molecule. They take advantage of a nonlinear coupling regime that appears when a fast rotating magnetic field is applied to a superparamagnetic bead immersed in a viscous fluid. In this work, we present the development of the technique and we compare it with other techniques capable of measuring the torque applied to the DNA molecule. In this proof of principle, we use standard electromagnets to achieve our experiments. Despite technical difficulties related to the present implementation of these electromagnets, the agreement of measurements with previous experiments is remarkable. Finally, we propose a simple way to modify the experimental design of electromagnets that should bring the performances of the device to a competitive level. (C) 2011 American Institute of Physics. [doi:10.1063/1.3531959]