Bioinspired multifunctional TiO2 hierarchical micro/nanostructures with tunable improved bone cell growth and inhibited bacteria adhesion

Abstract Two main origins of failure for hard tissue replacements are structural loosening and prosthetic implant infections (PIIs). Bioinspired multifunctional TiO2 hierarchical micro/nanostructures of conical-shaped TiO2 (CTO), regular TiO2 nanotubes (RTO) and irregular TiO2 nanotubes (ITO) with tunable improved cell growth and inhibited bacteria adhesion were synthesized. CTO and ITO samples indicated superhydrophilicity with contact angles of less than 5°. The MTT assay demonstrated excellent biological performance for RTO and CTO sample with 98.1% and 103.1% of cell viability, respectively. The bridging force for osteoblast cell attachment onto the synthesized porous coatings was presented as a possible mechanism. Ultimately, effect of different synthesized surfaces on both Gram-negative, Esherichia coli, and Gram-positive, Staphylococcus aureus, bacteria were estimated. The number of both Gram-negative and Gram-positive bacteria per field (NBPF) for RTO were calculated 31 and 42 respectively which were reduced more than approximately 7 and 6 times compared to the calculated NBPF of 222 and 258 for the untreated RT substrate. The recommended approach for bacteria adhesion inhibition without using antibiotics presents an auspicious solution to counteracting bacterial resistance to antibiotics.