Figure 1

(a) 3D-printed frame for PCL mesh formation. (b) PCL thread with diameter 100 µm was wound around the pegs of the frame and circular PCL sheets (diameter 12 mm) with an aperture were placed between the threads. Finally, the mesh was formed by “gluing” the threads together with pre-heated copper plates. (c) 100 µm-thick PCL supports with mesh pores for the hydrogel with a solid rim. (d) Mesh with different pore sizes ranging from 1.8 to 0-4 mm. (e) Different hydrogels were used to fill the PCL mesh pores depending on application: PEG-tetraacrylate-gelatin-methacrylate hydrogel, PEG-tetraacrylate hydrogel, or PEG-tetraacrylate-PEG-dimethacrylate hydrogel. (f) Mesh pores filled with 100 µm thick non-swelling PEG-4a hydrogel, the mesh support makes it possible to handle the fragile hydrogel membrane with tweezers. (g) Fluorescent image of mesh pores filled with hydrogel containing red fluorescent nanoparticles. The darker areas are PCL threads. (h) Photograph of the modified Transwell (top view) with the PCL mesh filled with hydrogel immediately after synthesis and having been submerged in cell media.