Micropatterned structures serving for primary microglia culturing. Microtopographic silicon masters are realized to replica-mold substrates on PDMS with pillar-shaped and line-grating geometries (width: 1500 nm, pitch: 3 μm, height: 550 nm). A. Scanning electron microscope (Zeiss EVO) images of PDMS pillar- shaped substrates. B. Scanning electron microscope images of Si master with line-grating structures. C. PDMS line-gratings at high magnification.