Nanofeature Size and Morphology of Tantalum Oxide Surfaces Control Osteoblast Functions

Abstract

Tantalum is one of the most corrosion-resistant materials and has mechanical properties that are suitable for orthopedic applications. However, tantalum exhibits bioinert characteristics and cannot promote the desired level of osseointegration with juxtaposed bone tissues. To enhance the bioactivity of tantalum, nanoscale surface modifications via anodization could be a potential approach. In this study, surface features having nanotubular, nanodimple, and nanocoral morphologies were fabricated onto tantalum by controlling anodization parameters. Aside from altering the surface morphology, nanotubular, nanodimple, and nanocoral feature sizes were precisely fine-tuned between the 20 and 140 nm range. The results indicated that anodized surfaces consisted of Ta2O5 and non-stoichiometric tantalum suboxide chemistry. Upon the anodization, surface area of the tantalum samples increased up to 2-fold, which was accompanied by up to a 3.5-folds increase in the nanophase surface roughness. Biological studies showed that anodized tantalum surfaces significantly enhanced protein adsorption and improved bone cell proliferation and spreading independently of the anodized surface morphology and feature size. Nanodimple surfaces having a 90 nm feature size promoted 50% more bone cell proliferation and 23% more cellular spreading compared to non-anodized tantalum. Nanodimple surfaces also enhanced alkaline phosphatase activity and increased Ca mineral deposition up to 5 weeks compared to non-anodized tantalum, indicating higher bioactivity. In this study, biological interactions of anodized tantalum surfaces having different morphologies and feature sizes were examined, for the first time, and the potential use of nanostructured tantalum was highlighted for orthopedic applications.

Anodized Nanostructured 316L Stainless Steel Enhances Osteoblast Functions and Exhibits Anti-Fouling Properties

“…Creating a nanostructured topography on implant surfaces is a promising strategy to improve the biological response and prevent bacterial colonization on 316L SS implant surfaces. , Anodic oxidation (anodization) is an electrochemical surface modification technique to form a nanostructured oxide layer on the surfaces of valve metals, including aluminum, , titanium, , zirconium, , etc. In the last decade, anodization of different metallic implant components received considerable attention due to it is simplicity and ability to obtain nanofeatures having different feature sizes and morphologies by changing the anodization parameters, i.e., voltage, time, etc. − For instance, our research group previously created nanopores, nanodimples (NDs), nanotubes, and nanocoral morphologies on tantalum surfaces and controlled the feature size of these morphologies between 20 and 140 nm to enhance the osteoblast (bone cell) functions on these surfaces . In another study, we formed nanotubular structures on titanium surfaces via anodization and controlled the feature size of these nanotubular structures between 25 and 140 nm.…”

“… 14 − 17 For instance, our research group previously created nanopores, nanodimples (NDs), nanotubes, and nanocoral morphologies on tantalum surfaces and controlled the feature size of these morphologies between 20 and 140 nm to enhance the osteoblast (bone cell) functions on these surfaces. 18 In another study, we formed nanotubular structures on titanium surfaces via anodization and controlled the feature size of these nanotubular structures between 25 and 140 nm. The nanotubular structures improved exosome secretion, which in turn stimulated the endothelial cell viability.…”

Development and properties of UV‐cured poly (propylene fumarate)/hydroxyapatite composites coatings as potential application for bone adhesive tape

“…Above all, the composite efficiently facilitated the proliferation of experimental cells in this study. Some relevant literature has demonstrated that hydroxyapatite can motivate the cell proliferation of human and animal osteoblasts 44–46 . In general, it can be concluded that the composite significantly enhanced cell proliferation.…”

“…Some relevant literature has demonstrated that hydroxyapatite can motivate the cell proliferation of human and animal osteoblasts. [44][45][46] In general, it can be concluded that the composite significantly enhanced cell proliferation.…”

Delivering Mechanical Stimulation to Cells: State of the Art in Materials and Devices Design

“…Finally, chemical treatments and chemical syntheses can also produce a variety of topographical features. For example, nanopore arrays can be fabricated by electrochemical anodization, [ 54b–d,77 ] micro/nanoscale roughness can be obtained by wet chemical etching, [ 53b,78 ] wire arrays can be synthesized by chemical vapor deposition, [ 55b,c,79 ] induced crystallization, [ 80 ] electrochemical polymerization [ 51b,81 ] and hydrothermal treatment. [ 55a,d,82 ] Chemical treatments and chemical syntheses are not confined to 2D surfaces, and thus hold great potential for introducing topographical features into 3D bulk and porous scaffolds.…”