Optical-driven vortex as a microparticle concentator

The light-driven optoelectronic vortex concept is firstly reported in this article. Utilizing illuminating light image to manipulate the liquid flow direction without any mechanic components is the feature of this design, named as optoelectroosmosis flow (OEOF). With the simple spin-coating process to form a thin organic photoconductive material, TiOPc, on the designed ITO pattern, the projected light pattern is able to generate dynamic virtual electrode on the substrate surface. Besides, the non-uniform electric field distribution would drive the ions moving with slip velocity. Furthermore, two light driven flows with different directions are able to form a clockwise or counter clockwise for microparticles concentration from non-illuminating toward illuminating region. This convenient approach of light-driven flow and microparticle concentration without any mechanical component enlarge the scope of liquid manipulation field.