X-ray studies of biological cells in microfluidic devices provide a method to probe cellular structures or structural changes at the molecular level in a precisely controlled environment. However, the device design and the used materials must be compatible with X-ray scattering techniques as well as the cell culture in the devices. For this purpose, we develop new types of X-ray compatible microfluidic devices, which are based on a UV-curable adhesive as a moldable material, and thin Kapton films and silicon nitride membrane windows as a growth substrate for cells and as a window material for X-rays. Using these devices, we perform scanning X-ray diffraction experiments with a nano-focused beam on fixed cells in buffer solution. In principle, these microfluidic devices also allow for X-ray studies on living cells.