UC Santa Cruz
Electro-Optical System For Anti-Brownian Electrokinetic (ABEL) Trapping In An Optofluidic Waveguide
- Author(s): Duttaroy, Anik
- Advisor(s): Schmidt, Holger
- et al.
Brownian motion presents a challenge to studying single bio-particles in a fluid. Traditionally, single bio-particles are trapped using optical traps, but the high optical powers required can damage bio-molecules under long-term study. We have rebuilt an electro-optical system that suppresses Brownian motion to trap a single particle. The system collects the optical signal of an excited particle in the trapping volume to track its location and applies an electrokinetic force via a feedback voltage to drive the particle towards an optical equilibrium point. We have achieved trap stiffness values of 99 nN/m for a 1 um polystyrene bead. The system uses optical powers three orders of magnitude less than optical traps, is cheaper compared to other published ABEL traps, and is simple to set up.