Novel hierarchical tantalum oxide-PDMS hybrid coating for medical implants: One pot synthesis, characterization and modulation of fibroblast proliferation.
Surface properties such as morphology, roughness and charge density have a strong influence on the interaction of biomaterials and cells. Hierarchical materials with a combination of micron/submicron and nanoscale features for coating of medical implants could therefore have significant potential to modulate cellular responses and eventually improve the performance of the implants. In this study, we report a simple, one pot wet chemistry preparation of a hybrid coating system with hierarchical surface structures consisting of polydimethylsiloxane (PDMS) and tantalum oxide. Medical grade, amine functional PDMS was mixed with tantalum ethoxide which subsequently formed Ta2O5in situ through hydrolysis and condensation during coating process. The coatings were characterized by SEM, EDS, XPS, confocal scanning microscopy, contact angle measurement and in vitro cell culture. Varying PDMS and tantalum ethoxide ratios resulted in coatings of different surface textures ranging from smooth to submicro- and nano-structured. Strikingly, hierarchical surfaces containing both microscale (1-1.5μm) and nanoscale (86-163nm) particles were found on coatings synthesized with 20% and 40% (v/v) tantalum ethoxide. The coatings were similar in term of hydrophobicity but showed different surface roughness and chemical composition. Importantly, higher cell proliferation was observed on hybrid surface with hierarchical structures compared to pure PDMS or pure tantalum oxide. The coating process is simple, versatile, carried out under ambient condition and requires no special equipment.
Queensland University of Technology (QUT), Australia; Department of Chemical and Biomolecular Engineering, The Particulate Fluid Processing Centre, The University of Melbourne, Victoria 3010, Australia. Electronic address: phong.tran@qut.edu.au.
Phong A
PA
Tran
School of Engineering, RMIT University, Melbourne, Victoria 3000, Australia.
Kate
K
Fox
School of Science, RMIT University, Melbourne, Victoria 3000, Australia. Electronic address: nhiem.tran@rmit.edu.au.
Nhiem
N
Tran
D016475:3T3 Cells; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects*; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis* / Q000494:pharmacology; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D008422:Materials Testing; D051379:Mice; D010087:Oxides / Q000737:chemistry*; D019736:Prostheses and Implants; D013499:Surface Properties; D013635:Tantalum / Q000737:chemistry*
D020099:Coated Materials, Biocompatible; D004129:Dimethylpolysiloxanes; D010087:Oxides; C013830:baysilon; D013635:Tantalum; C078151:tantalum oxide
Coating; Hierarchical structure; Implants; Surface treatment