Fig. 3

Cell culture on inverse opal films stretched at different directions. a PC12 cells cultured on 0°-stretched inverse opal films: (i) Schematic diagrams, (ii) immunofluorescence image, (iii) SEM image, and (iv) angle distribution of neurites of PC12 cells. b PC12 cells cultured on 15°-stretched inverse opal films: (i) Schematic diagrams, (ii) immunofluorescence image, (iii) SEM image, and (iv) angle distribution of neurites of PC12 cells. c PC12 cells cultured on 30°-stretched inverse opal films: (i) Schematic diagrams, (ii) immunofluorescence image, (iii) SEM image, and (iv) angle distribution of neurites of PC12 cells. d PC12 cells cultured on 45°-stretched inverse opal films: (i) Schematic diagrams, (ii) immunofluorescence image, (iii) SEM image, and (iv) angle distribution of neurites of PC12 cells. Scale bars are 50 μm in all (ii) and (iii)