Diamond-like carbon (DLC) layers are known for their high corrosion and wear resistance, low friction, and high biocompatibility. However, it is often necessary to dope DLC layers with additional chemical elements to strengthen their adhesion to the substrate. Ti-DLC layers (doped with 0.4, 2.1, 3.7, 6.6, and 12.8 at.% of Ti) were prepared by dual pulsed laser deposition, and pure DLC, glass, and polystyrene (PS) were used as controls. In vitro cell-material interactions were investigated with an emphasis on cell adhesion, proliferation, and osteogenic differentiation. We observed slightly increasing roughness and contact angle and decreasing surface free energy on Ti-DLC layers with increasing Ti content. Three-week biological experiments were performed using adipose tissue-derived stem cells (ADSCs) and bone marrow mesenchymal stem cells (bmMSCs) in vitro. The cell proliferation activity was similar or slightly higher on the Ti-doped materials than on glass and PS. Osteogenic cell differentiation on all materials was proved by collagen and osteocalcin production, ALP activity, and Ca deposition. The bmMSCs exhibited greater initial proliferation potential and an earlier onset of osteogenic differentiation than the ADSCs. The ADSCs showed a slightly higher formation of focal adhesions, higher metabolic activity, and Ca deposition with increasing Ti content.

• Keywords
• adipose tissue-derived stem cells (ADSCs), biocompatibility, bone marrow mesenchymal stem cells (bmMSCs), diamond-like carbon layer (DLC), osteogenic differentiation, titanium,
• MeSH
• Arthroplasty, Replacement * MeSH
• Cell Differentiation MeSH
• Mesenchymal Stem Cells * metabolism   MeSH
• Osteogenesis MeSH
• Surface Properties MeSH
• Titanium chemistry   MeSH
• Carbon chemistry   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Titanium MeSH
• Carbon MeSH

Diamond-like carbon (DLC) thin films are promising for use in coating orthopaedic, dental and cardiovascular implants. The problem of DLC layers lies in their weak layer adhesion to metal implants. Chromium is used as a dopant for improving the adhesion of DLC films. Cr-DLC layers were prepared by a hybrid technology, using a combination of pulsed laser deposition (PLD) from a graphite target and magnetron sputtering. Depending on the deposition conditions, the concentration of Cr in the DLC layers moved from zero to 10.0 at.%. The effect of DLC layers with 0.0, 0.9, 1.8, 7.3, 7.7 and 10.0 at.% Cr content on the adhesion and osteogenic differentiation of human osteoblast-like Saos-2 cells was assessed in vitro. The DLC samples that contained 7.7 and 10.0 at.% of Cr supported cell spreading on day 1 after seeding. On day three after seeding, the most apparent vinculin-containing focal adhesion plaques were also found on samples with higher concentrations of chromium. On the other hand, the expression of type I collagen and alkaline phosphatase at the mRNA and protein level was the highest on Cr-DLC samples with a lower concentration of Cr (0-1.8 at.%). We can conclude that higher concentrations of chromium supported cell adhesion; however DLC and DLC doped with a lower concentration of chromium supported osteogenic cell differentiation.

• MeSH
• Alkaline Phosphatase metabolism   MeSH
• Coated Materials, Biocompatible MeSH
• Cell Adhesion * MeSH
• Cell Differentiation * MeSH
• Cell Line MeSH
• Chromium chemistry   MeSH
• Diamond chemistry   MeSH
• Focal Adhesions MeSH
• Collagen Type I metabolism   MeSH
• Metals chemistry   MeSH
• Lasers MeSH
• Humans MeSH
• RNA, Messenger metabolism   MeSH
• Osteoblasts cytology   MeSH
• Osteogenesis MeSH
• Surface Properties MeSH
• Gene Expression Profiling MeSH
• Talin chemistry   MeSH
• Carbon chemistry   MeSH
• Vinculin metabolism   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Alkaline Phosphatase MeSH
• Coated Materials, Biocompatible MeSH
• Chromium MeSH
• Diamond MeSH
• Collagen Type I MeSH
• Metals MeSH
• RNA, Messenger MeSH
• Talin MeSH
• Carbon MeSH
• Vinculin MeSH