Fig. 2
From: Protein disorder–order interplay to guide the growth of hierarchical mineralized structures
Bulk characterization. Organic–inorganic interactions within the bulk of the mineralized membranes. SEM observations revealed a the abundant presence of a dense pattern of spherulite-like structures with b a granulated central region at the bulk of the membranes’ cross-sections, which c template the growth of fluorapatite spherulites. d Near the membrane surface, mineralized structures with nanocrystals grow vertically toward the surface of the membrane. DDC-SEM images of e the core of fluorapatite spherulite structures located closer to the surface of the membrane and f deeper within the bulk of the membrane, revealing a thin low-density material (green) surrounding a denser (orange) one. g Backscattered electron (BSE) image showing brighter areas at the center of the structures, indicating the presence of mineral deep within the membrane. h, i FIB sectioning of the hierarchically mineralized structure resolving the deeper mineralized core structures located underneath the center of the structures. j, kTEM images from a FIB milling lift-out of a mineralized structure illustrating j the change in growth direction of the nanocrystals from parallel to the surface towards the bulk of the ELR membrane, and k the growing interface between the flat-ended inorganic crystals and the organic ELR material. l HRTEM image of a single fluorapatite crystal showing its growth orientation and crystal lattices. m SAED and n FFT analyses showing the characteristic diffraction pattern of the fluorapatite crystals (left) and its 10° co-alignment, respectively. Scale bars: a 2 µm; b, c 1 µm; d 2 µm; e, f 200 nm; g 20 µm; h, i 5 µm; j 200 nm; k 100 nm; l 10 nm; m 3 nm−1
