Fig. 5.

Physical characterization of the mineralized membranes.(A) Illustration depicting regions where nanoindentation tests were conducted on the edges of the elliptical-shaped mineralized structures grown on Channel (2, 2) including in the direction parallel and perpendicular to the direction of the channels. (B) Graph summarizing the Young's modulus (E) measurements at different locations on the circular- and elliptical-shaped mineralized structures grown on Channel (0, 0) and Channel (2, 2), respectively. (C) FTIR spectra and (D) XRD pattern confirming the presence of apatite structures and the fluorapatite nature of the crystalline phase, respectively, in the mineralized ELR membrane. (E) TEM image showing a single nanocrystal of 40–50 nm thick flat-ended geometry and (F, G) its corresponding fast Fourier transform (FFT) pattern with typical fluorapatite hexagonal morphology growing along the c-axis. (B) ∗ denotes significant difference between E values for edge parallel vs. edge perpendicular; p < 0.05, estimated using t-test in GraphPad Prism software.