Fig 1.
Scheme of the preparation of hybrid fullerene C60/metal composites.
Deposition rates: DR(M) = DR(C60) ~ 1 nm/min. Temperatures during deposition: RT.
Fig 2.
Raman spectra (between 1100–1800 cm-1) of the fresh (A) and aged (B) C60/Ti composites with various Ti concentrations (low: 25%, medium: 45%, high: 70%).
For comparison, a spectrum from the C60 standard is shown.
Fig 3.
AFM images of the surface morphology on the prominences of the fresh and aged C60/Ti composites with various Ti concentrations (low: 25%, medium: 45%, high: 70%).
Table 1.
Fig 4.
Raman spectrum of thin films formed in Petri dishes by evaporating water solutions after incubation of C60/Ti composites with a low (A), medium (B) and high (C) content of Ti for 24 hours and then for another 48 hours.
No Ag(2) vibration mode (i.e., no presence of C60) was confirmed.
Fig 5.
Static water drop contact angle of fresh and aged C60/Ti composites with various Ti concentrations (low: 25%, medium: 45%, high: 70%).
* significant difference between fresh and aged layers; p ≤ 0.05.
Fig 6.
Numbers of human osteoblast-like MG-63 cells on fresh or aged C60/Ti composites with various Ti concentrations (low: 25%, medium: 45%, high: 70%) on day 1 (A), 3 (B) and 7 (C) after seeding.
GS: microscopic glass coverslips, a reference material. No significant differences among the experimental groups were found.
Fig 7.
Morphology of human osteoblast-like MG-63 cells on day 3 after seeding on fresh and aged C60/Ti composites with various concentrations of Ti (low: 25%, medium: 45%, high: 70%).
GS: microscopic glass coverslips, reference material.
Fig 8.
Metabolic activity measured by the XTT test per culture of human osteoblast-like MG-63 cells on day 7 after seeding on fresh and aged C60/Ti composites with various Ti concentrations (low: 25%, medium: 45%, high: 70%).
GS: microscopic glass coverslips, a reference material. No significant differences among the experimental groups were found.
Fig 9.
Viability of human osteoblast-like MG-63 cells, measured by the trypan blue exclusion test on day 7 after seeding on fresh and aged C60/Ti composites with various Ti concentrations (low: 25%, medium: 45%, high: 70%).
GS: microscopic glass coverslips, reference material. No significant differences among the experimental groups were found.
Fig 10.
Flow cytometry of the marker of DNA damage response: gamma-H2AX in human osteoblast-like U-2 OS cells on fresh (A) and aged (B) C60/Ti composites with various Ti concentrations (low: 25%, medium: 45%, high: 70%).
GS: microscopic glass coverslips, reference material; GS+NCS: positive control to phosphorylation of histon H2AX (gamma-H2AX), induced by 1 hour incubation of U-2 OS in neocarzinostatin (NCS; 700ng/mL). M19 and M1 define the percentage of cells with no increase in DNA damage (obtained from cells growing on the reference material, GS); M20 and M2 define the percentage of cells with an increased DNA damage response represented by enhanced phosphorylation of histon H2AX (obtained from cells incubated with NCS).
Fig 11.
Immunofluorescence staining of markers of a DNA damage response: 53BP1 (green) and gamma-H2AX (red) in human osteoblast-like U-2 OS cells on fresh and aged C60/Ti composites with various Ti concentrations (low: 25%, medium: 45%, high: 70%).
GS: microscopic glass coverslips, reference material; GS+NCS: positive control of DNA damage response induced by 1 hour incubation of U-2 OS in neocarzinostatin (NCS; 700ng/mL).