In this doctoral work, the aim is to explore fundamentally new ways for the electrical/optical control of microfluidic systems by the use of anisotropic fluids, namely nematic liquid crystals. It is intended to exploit that the local average molecular orientation in nematics can be changed by electric field and light. Since the orientation is coupled to flow and the effective viscosity is orientation dependent, tunable flow control in microfluidic environment is expected. Furthermore, electro-hydrodynamic instabilities in nematics can result in switchable vortex flow/turbulence. We intend to explore and understand the interplay between the flow and electric field driven nematic reorientation effects with emphasis on electroconvection in various microfluidic geometries, and exploit these for flow regulation, deflection, mixing, and sorting. The use of polarized light offering contactless control without requiring electrodes is also to be investigated. Experiments will be performed on microfluidic chips prepared by direct laser writing based soft lithography. The flow/orientation fields will be determined by various microscopy techniques (polarizing, polarimetric, fluorescence). The ultimate goal is to establish a new toolbox of liquid crystal based microfluidic actuators, and investigate their characteristics/applicability on water inclusions in liquid crystal carrier fluid for applications in droplet based microfluidics used e.g. in biotechnology.