The rationale is that the hydroxyl and/or amide groups present in the 4SC-202 cell line silk fibroin can capture the calcium and phosphorous groups present in HAp NPs, thereby resulting in the covering of apatite nuclei to X-ray

beams to be detected at lower concentrations. However, comparing the higher content counterparts obtained after the addition of HAp NPs, (i.e., silk + 50% HAp NPs) the spectra possess reasonably extra peaks located at the same diffraction angles as that mentioned in the JCPDS database [27, 28]. Furthermore, the graph shows the spectra of nanofibers modified with lower concentrations of HAp NPs not showing strong intensity peaks than the higher concentrations. This may be the limitation with XRD technique or may be

due to the masking of HAp crystals by silk fibroin. In order to understand the effect caused by the addition of HAp NPs on the nature of silk fibroin nanofibers and to simultaneously put more light on the crystallinity of silk fibroin in nanofibers, the inset in Figure 11 shows the diffraction peaks obtained at 2θ values from 10° to 28°. The broad diffraction peak in this inset shows the scatter peak with 2θ values of 21.9° which is indicating typical amorphous scattering pattern of amorphous JQ-EZ-05 research buy silk [29]. Interestingly, it can be observed that this broad peak forms strong peak with increased intensity with nanofibers modified with HAp, which further indicates enrichment in the transformation from randomly arranged to crystalline βchain structure, in the case of nanofibers modified with HAp NPs. Figure 11 The XRD results of the obtained nanofibers at 2 θ values from 10° to 60°. The inset in the figure shows the 2θ value from 10° to 28°. Lenvatinib manufacturer pristine nanofibers (spectrum A), silk fibroin nanofibers modified with 10% HAp NPs (spectrum B), 30% HAp NPs (spectrum C), and 50% HAp NPs (spectrum Non-specific serine/threonine protein kinase D). FT-IR can be used as an efficient tool to investigate

the structural confirmations because of the knowledge of the vibration origins of the amide bonds, the sensitivity of some of these band positions to conformation, and the possibility of predicting band positions for a given helical or extended conformation [30]. The changes occurred on the band positions for pristine, and the one modified with HAp NPs is expressed in Figure 12. The vibrations occurred in pristine nanofiber due to amide Ι, amide II, and amide III bands can be seen at 1,626 cm−1, 1,516 cm−1, and 1,232 cm−1 which confirm the nature of the silk fibroin in the nanofibers. Moreover, nanofibers modified with HAp also showed the presence of these amide bands; however, there was a downshift of 1 to 2 units for amide Ι and amide II bands. The reason is to show that this shift can be attributed to conformational changes occurred in the silk fibroin from random coil structure to β-sheet confirmation due to the incorporation of HAp NPs [31, 32].