Numerical simulation of an optical chromatographic separator.

Optical chromatography achieves microscale optical manipulation through the balance of optical and hydrodynamic forces on micron sized particles entrained in microfluidic flow traveling counter to the propagation of a mildly focused laser beam. The optical pressure force on a particle is specific to each particle's size, shape and refractive index. So far, these properties have been exploited in our lab to concentrate, purify and separate injected samples. But as this method advances into more complex optofluidic systems, a need to better predict behavior is necessary. Here, we present the development and experimental verification of a robust technique to simulate particle trajectories in our optical chromatographic device. We also show how this new tool can be used to gather better qualitative and quantitative understanding in a two component particle separation.