Evaluation of trapping efficiency of optical tweezers by dielectrophoresis.
A relatively new method for measuring optically induced forces on microparticles and cells, different from the conventional Brownian motion and viscous drag force calibration methods widely used, is introduced. It makes use of the phenomenon of dielectrophoresis for the calibration of optical tweezers through the dielectrophoretic force calculations. A pair of microelectrodes is fabricated by photolithography on a microscope slide and it is connected to a high-frequency generator. The calibration of the optical tweezers setup is performed by the manipulation of polystyrene beads and yeast cells. Calibration diagrams of the transverse forces versus power are deduced for different cell radii and numerical apertures of the objective lenses. The optical system and the related technique provide a fast and easy method for optical tweezers calibration.
Papagiakoumou
Eirini
E
National Technical University of Athens, Zografou Campus, School of Applied Mathematical and Physical Sciences, Physics Department, 15780 Athens, Greece. papageir@mail.ntua.gr
Pietreanu
Dorel
D
Makropoulou
Mersini I
MI
Kovacs
Eugenia
E
Serafetinides
Alexander A
AA
D002138:Calibration; D046209:Electrophoresis, Microchip / Q000295:instrumentation* / Q000379:methods*; D019544:Equipment Failure Analysis / Q000295:instrumentation* / Q000379:methods*; D008846:Micromanipulation / Q000295:instrumentation / Q000379:methods*; D009038:Motion; D055095:Optics and Photonics / Q000295:instrumentation*; D013314:Stress, Mechanical; D014159:Transducers