Modified nanoporous titanium dioxide layers for drug delivery and cell culturing

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Anna Pawlik, Grzegorz D Sulka, Habil and Robert Socha

Jagiellonian University, Poland
Polish Academy of Sciences, Poland

: Biomater Med Appl

Abstract

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Statement of the Problem: Now-a-days, most of implants are made of titanium and its alloy. However, the process of chemical bonding between the biomaterial and surrounding bones is long-lasting. In addition, periprosthetic joint infections and insufficiency of the conventional antibiotic therapies may lead to the implant failure. Method: The Anodic Titanium Dioxide (ATO) layers were synthesized via a three-step anodization process in an ethylene glycolbased solution. They were alkali treated by immersing in a 0.5 M sodium hydroxide solution. In order to obtain the anatase phase the samples were annealed at 400 °C. The non-annealed and annealed NaOH-modified layers were functionalized with different silane derivatives, (3-aminopropyl)triethoxysilane (APTES), (3-glycidyloxypropyl)trimethoxysilane (GPTMS) and (3-mercaptopropyl) trimethoxysilane (MPTMS). The modified samples were characterized by using scanning electron microscopy and X-ray photoelectron spectroscopy. Ibuprofen was used as a model drug in the drug delivery studies. The drug was loaded inside the nanopores and released in a phosphate buffer solution at 37 °C. The Desorption-Desorption-Diffusion (DDD) model was fitted to the obtained drug release profiles. For biological studies the osteoblast-like cell line MG-63 was used. The number of viable cells after 2, 24 and 72 hours were determined by the MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay. The morphology of adhered osteoblast-like cells line MG-63 was investigated using fluorescence and scanning electron microscopies. Findings: The modification of anodic TiO2 layers inhibited the drug release process. In addition, the functionalization led to the improvement of the cell response. The release process from annealed samples was slower than from non-annealed. However, the number of viable cells was higher on the non-annealed layers. Conclusion: The modification of nanoporous titanium dioxide layers affects the drug delivery process and cell response. It is possible to improve both aspects by the two-step modification of amorphous TiO2 samples with NaOH and silane derivatives.

Biography

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E-mail: pawlika@chemia.uj.edu.pl