Microfluidics is a multidisciplinary field of studies aiming to manipulate fluids that are geometrically constrained to a small scale at which surface forces dominate over volumetric forces. Research on microfluidics has started in the 1980s and since then it has been widely developed in various branches of science . Small size is a defining feature of microfluidic devices, but there are surely other valuable advantages of moving from macro to microscale. Tiny instantaneous volumes (micro to picoliters) associated with microfluidics determine that mass transport is dominated by diffusion . Because of that, fluid mixing occurs in a controllable fashion and laminar flow regimes are fully developed. The laminar nature of flow in turn ensures that particle or fluid motions are well-defined and thus they can be engineered towards a particular purpose. For example, the flow may be designed to direct and based on their molecular structure distribute a stream of molecules to specific streamlines, e.g., surface-specific antigens, or depending on their physical properties (size) or electrical properties .