Structural investigations showed that the diameter of the fibers is nearly uniform, about 500-1000 nm, but too many beads were formed and spheres developed with a few hundred microns in diameter (Fig. 2.12a). The EDS confirmed that the fibers contain the HAp, but the element mapping shows that the distribution of it is not homogenous. The EDS measurement showed C (found in CA), O (CA and HAp), P (HAp), Mg, S (HAp-eggshell trace element) Si (sample holder) and Al (sample cover) compounds. According to the Ca (Fig. 2.12b)) and P element maps (Fig. 2.12c)) the HAP presence in 1-2 micrometer sized clusters. The presence of Ca and P can be in 1-2 micron clusters. The distribution of O (Fig. 2.12d)) is homogenous, because the CA contains it too.

In our study, the mixing parameters were between 15 and 25 w/w% solid mate­rial (HAp+CA), increasing the concentration varied of Hap+CA resulted larger fiber diameter and fewer beads 47. Using more than 30 w/w% and less than 5 w/w% it was impossible to produce fibers. Applying 20 w/w% acetic-acid electrospinning process generated uniform fiber diameter. Using any other w/w% acetic-acid caused larger fibers diameter and more beads. It could be concluded that the composition of the solution has the most striking influence on the morphology of the final mats.