In many applications, such as in microfluidics, in printing and coating technologies, and in lab-on-a-chip devices, wetting properties play an important role. Wetting properties depend strongly on surface morphology and on the fluids. Momentum, heat, and matter transfer have to be taken into account in this context. To characterise these phenomena, in this project the three-phase contact line will be characterised in microfluidic systems by Raman spectroscopy. Usually the microchannels are prepared by lithography in PDMS, but here another possibility by 3D printing the channels is tried. In this way the sample preparation is shortened and the suface modification can be obtained in the same step. Different fluid mixtures will be characterised on differently modified surfaces. The project is part of the CRC 1194, which studies the interaction between wetting and transport phenomena.