Multi-channel LFC. (a) 3D design of a multi-channel LFC. (b) Visualization of separation of flow in the multi-channel LFC. The middle channel contains a colour-less buffer solution. (c) Quality of separation of flow as a function of flow velocity (mm/s). (d) Separation of polystyrene microspheres between two buffer streams running at flow velocity of 0.4 mm/s.