Guided proliferation and bone-forming functionality on highly ordered large diameter TiO2 nanotube arrays.
Ruopeng Zhang1, Hongliu Wu1, Jiahua Ni1
1State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, P R China.
Summary
Titanium dioxide (TiO2) nanotubes with diameters between 100-200 nm promote optimal bone-forming activity. Larger diameters enhance cell proliferation but reduce elongation and alkaline phosphatase activity, guiding orthopedic implant design.
Area of Science:
- Biomaterials Science
- Cell Biology
- Nanotechnology
Background:
- Previous studies showed enhanced osteoblast functions on TiO2 nanotubes <100 nm.
- Osteoblast adhesion, proliferation, and alkaline phosphatase (ALP) activity are key for bone regeneration.
Purpose of the Study:
- To investigate MC3T3-E1 cell behavior on TiO2 nanotube arrays with larger diameters (150-470 nm).
- To determine the optimal TiO2 nanotube diameter range for bone-forming activity.
Main Methods:
- Fabrication of highly ordered TiO2 nanotube arrays via high voltage anodization.
- Controlled variation of nanotube diameters from 150 nm to 470 nm.
- Assessment of MC3T3-E1 cell elongation, proliferation, and ALP activity on different nanotube diameters.
Main Results:
- A contrast was observed between cell proliferation and elongation trends with varying nanotube diameters.
- Maximal cell elongation (10:1) and minimal cell number occurred at 150 nm diameter.
- Maximal cell number and minimal elongation were observed at 470 nm diameter.
- ALP activity peaked at 150 nm and decreased significantly with increasing diameter.
Conclusions:
- A narrow diameter range (100-200 nm) of TiO2 nanotubes is optimal for inducing bone-forming activity.
- Controlling TiO2 nanotube diameter allows for tailored orthopedic implant design, potentially enabling regional control of cell proliferation and bone formation.
