Interaction of nanostructured TiO2 biointerfaces with stem cells and biofilm-forming bacteria

- TiO2 nanotubes with different diameters were made by electrochemical anodization.
- No impact on biofilm formation was detected using B. cereus and P. aeruginosa.
- Embryonic and mesenchymal stem cells behaviour showed remarkable differences.
- Cardiomyocytes were not able to adhere and grow.
- Behaviour of various cells was correlated to the diameter of TiO2 nanotubes.

Nanostructured TiO2 nanotubes (NTs) of diameters from 15 to 100 nm were fabricated by an electrochemical anodization process. Biofilm-positive strains of Bacillus cereus and Pseudomonas aeruginosa behaved similarly on all TiO2 NTs as well as on native titanium (Ti) foil. The adhesion and growth of mesenchymal stem cells (MSc), embryonic stem cells (ESc), and pure cardiomyocytes derived from ESc exhibited significant differences. MSc as well as ESc were, in contrast to cardiomyocytes, able to adhere, and grow on TiO2 NTs. A correlation between NTs diameter and cell behaviour was however observed in the case of MSc and ESc. MSc were not in a physiological state in the case of 100 nm TiO2 NTs, while ESc were not able to grow on 15 nm TiO2 NTs. It can be stated that these differences can be assigned to different diameters of the NTs but not to the chemistry of the surface. This is the first study describing the comprehensive behaviour of both eukaryotic and prokaryotic cells on TiO2 NTs. On the basis of obtained results, it can be concluded that new generation of medical devices providing selective cell behaviour can be fabricated by optimizing the nanoscale morphology of TiO2.