Thallium/vanadate co-substitutions through hydroxyapatite/polycaprolactone nanofibrous scaffolds for biomedical domains

Highlights: • Nanofibrous scaffold containing polycaprolactone (PCL) was encapsulated with co-doped hydroxyapatite (HAP). • The modification of HAP was carried out using co-doped thallium (Tl⁺)/vanadate ($V{O}_4^{3-})$. • The surface morphology indicated that the scaffolds were formed in networked nanofibers. • The mechanical properties showed that the toughness was enhanced owing to the encapsulation and modification. • The antibacterial potency of nanofibrous scaffold was enhanced against E. coli and S. aureus. Polymer-based electrospun nanofibrous scaffolds containing polycaprolactone (PCL) were encapsulated with co-doped hydroxyapatite (HAP). The modification of HAP includes co-doped thallium (Tl⁺)/vanadate ($V{O}_4^{3-})$ at different contributions of Tl⁺ ions. The obtained powdered and nanofibrous phases have been investigated upon their structure, morphology, and microstructure. The investigation of the surface morphology indicated that the scaffolds were formed in networked nanofibers with diameters around 0.2–0.8 μm to 43–80 nm for the lowest and the highest Tl ions contents through nanofibers. Besides, the maximum height of the roughness (R_t) increased from 190.2 to 242.7 nm for the powdered compositions, while it started from 395.9 nm and increased to 861.0 nm for the nanofibers scaffolds. Furthermore, the mechanical properties were tested and showed that the toughness increased from 0.56 ± 0.11 to 2.52 ± 0.83 MJ/m³. The contact angle was measured and exhibited a decreasing behavior starting from 101.2 ± 2.5 to 87.6 ± 4.3°. In addition, the antibacterial potency was examined, and the inhibition zone increased up to 21.4 ± 1.1 and 20.4 ± 1.2 mm against E. coli and S. aureus, respectively. The in vitro culturing of human fibroblasts cell line through the scaffolds showed that the cells were spread and grew robustly upon the compositional variation.