Physical and biological changes associated with the doping of carbonated hydroxyapatite/polycaprolactone core-shell nanofibers dually, with rubidium and selenite

Publication date: Available online 22 February 2020Source: Journal of Materials Research and TechnologyAuthor(s): M.K. Ahmed, Reem Al-Wafi, S.F. Mansour, S.I. El-dek, Vuk UskokovićAbstractElectrospun selenium-containing carbonated hydroxyapatite/polycaprolactone (CHAP/PCL) core/shell nanofibers were synthesized at different contents of Rb+ as a dopant in the ceramic phase. Microstructural, morphological and mechanical properties of the nanofibers were analyzed as a function of the stoichiometric content of Rb+ ions defined by the parameter x in [RbxCa(10-0.5x)(PO4)5.8(SeO3)0.2(OH)2]/PCL (0 ≤ x ≤ 0.8). Rb+ ions were incorporated inside the CHAP crystal lattice, where they induced crystal growth in the preferred c-axis direction. They also induced internal disordering, leading to reduced crystallinity. High-resolution TEM imaging demonstrated that the fibers had the form of tubes internally filled with rod-shaped CHAP nanoparticles, whose size increased from 50 to 70 nm on average as the result of doping with Rb+. The nanoparticles without any Rb+, at x = 0, were aligned well with the fiber curvature, but this alignment diminished as the fibers became more oblique at higher contents of Rb+. The attachment of human fibroblasts on the nanofibers was slightly enhanced at higher Rb+ contents. This effect was tied to an increase in the surface roughness of the composite with the amount of Rb+ in the CHAP phase, conforming to the finding that nanoparticles accommodating mo...
Source: Journal of Materials Research and Technology - Category: Materials Science Source Type: research