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

High-density polyethylene (PE) foils were modified by an Ar(+) plasma discharge and subsequent grafting with biomolecules, namely glycine (Gly), polyethylene glycol (PEG), bovine serum albumin (BSA), colloidal carbon particles (C) or BSA and C (BSA + C). As revealed by atomic force microscopy (AFM), goniometry and Rutherford Backscattering Spectroscopy (RBS), the surface chemical structure and surface morphology of PE changed dramatically after plasma treatment. The contact angle decreased for the samples treated by plasma, mainly in relation to the formation of oxygen structures during plasma irradiation. A further decrease in the contact angle was obvious after glycine and PEG grafting. The increase in oxygen concentration after glycine and PEG grafting proved that the two molecules were chemically linked to the plasma-activated surface. Plasma treatment led to ablation of the PE surface layer, thus the surface morphology was changed and the surface roughness was increased. The materials were then seeded with vascular smooth muscle cells (VSMC) derived from rat aorta and incubated in a DMEM medium with fetal bovine serum. Generally, the cells adhered and grew better on modified rather than on unmodified PE samples. Immunofluorescence showed that focal adhesion plaques containing talin, vinculin and paxillin were most apparent in cells on PE grafted with PEG or BSA + C, and the fibres containing alpha-actin, beta-actin or SM1 and SM2 myosins were thicker, more numerous and more brightly stained in the cells on all modified PE samples than on pristine PE. An enzyme-linked immunosorbent assay (ELISA) revealed increased concentrations of focal adhesion proteins talin and vinculin and also a cytoskeletal protein beta-actin in cells on PE modified with BSA + C. A contractile protein alpha-actin was increased in cells on PE grafted with PEG or Gly. These results showed that PE activated with plasma and subsequently grafted with bioactive molecules and colloidal C particles, especially with PEG and BSA + C, promotes the adhesion, proliferation and phenotypic maturation of VSMC.

• Keywords
• bioactivity, biocompatibility, plasma irradiation, tissue engineering and reconstruction,
• MeSH
• Actins metabolism   MeSH
• Aorta cytology   MeSH
• Cell Adhesion drug effects   MeSH
• Glycine pharmacology   MeSH
• Rats MeSH
• Cells, Cultured MeSH
• Oxygen metabolism   MeSH
• Microscopy, Atomic Force MeSH
• Polyethylene chemistry   pharmacology   MeSH
• Polyethylene Glycols chemistry   pharmacology   MeSH
• Cell Proliferation drug effects   MeSH
• Serum Albumin, Bovine pharmacology   MeSH
• Cattle MeSH
• Muscle, Smooth, Vascular cytology   drug effects   metabolism   MeSH
• Carbon chemistry   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Cattle MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Actins MeSH
• Glycine MeSH
• Oxygen MeSH
• Polyethylene MeSH
• Polyethylene Glycols MeSH
• Serum Albumin, Bovine MeSH
• Carbon MeSH