Binding of plasma proteins to titanium dioxide nanotubes with different diameters

Abstract

Titanium and titanium alloys are considered to be one of the most applicable materials in medical devices because of their suitable properties, most importantly high corrosion resistance and the specific combination of strength with biocompatibility. In order to improve the biocompatibility of titanium surfaces, the current report initially focuses on specifying the topography of titanium dioxide (TiO 2 ) nanotubes (NTs) by electrochemical anodization. The zeta potential (ζ-potential) of NTs showed a negative value and confirmed the agreement between the measured and theoretically predicted dependence of ζ-potential on salt concentration, whereby the absolute value of ζ-potential diminished with increasing salt concentrations. We investigated binding of various plasma proteins with different sizes and charges using the bicinchoninic acid assay and immunofluorescence microscopy. Results showed effective and comparatively higher protein binding to NTs with 100 nm diameters (compared to 50 or 15 nm). We also showed a dose-dependent effect of serum amyloid A protein binding to NTs. These results and theoretical calculations of total available surface area for binding of proteins indicate that the largest surface area (also considering the NT lengths) is available for 100 nm NTs, with decreasing surface area for 50 and 15 nm NTs. These current investigations will have an impact on increasing the binding ability of biomedical devices in the body leading to increased durability of biomedical devices.

Cell investigation into the biocompatibility of adult human dermal fibroblasts with PCL nanofibers/TiO2 nanotubes on the surface of Ti–30Ta alloy for biomedical applications

“…28 Nowadays, the layers of nanotubes biologically embedded in the metal surface by the anodization process are studied for surface modifications because of their chemical stability and structural properties. 25,36 The nanotubes of the TiO 2 layer modify the roughness of the surface and increase the surface area. 6,27,37,38 SEM images (See Figure 1A) show the vertical nanotubes of TiO 2 monolayer self-ordered on the Ti-30Ta alloy surface.…”

“…The layer of nanotubes has a different level of length due to alloy composition. 25,[39][40][41] The diameter of the nanotubes ranges between 80 and 100 nm. 42 According to Gongadze and Iglič, the diameter of nanotubes can have consequences on the biological response.…”

“…42 According to Gongadze and Iglič, the diameter of nanotubes can have consequences on the biological response. 43 Current researches 25,28,42,[44][45][46][47] have studied biomimetic surface modifications. Among the surface treatments, the electrospinning technique of biocompatible polymer PCL has been shown to be attractive for bone regeneration.…”

“…[17][18][19][20][21][22][23][24] Also, the nanotopography that mimics the natural tissue architecture has been shown to respond favorably with cellular interactions and further tissue formation. 25,26 In previous studies, Capellato et al demonstrated the efficiency of the use of TiO 2 nanotube containing surfaces to increase cell proliferation 27 and Bayram et al investigated the association of an increased interest in nanoscale properties and technologies. Moreover, the use of biocompatible polymers for the viability of cell growth is a promising alternative to improve osseointegration.…”

Photocatalytic Treatment of Paracetamol Using TiO2 Nanotubes: Effect of pH

“…The graph of the zeta potential (Figure 4) shows the variation of the zeta potential of paracetamol and the catalyst, with the pH of the medium. The curves intersect at pH 6.5; a value at which the paracetamol molecule is not ionized and the surface charge of TiO 2 is close to zero [41].…”