title: Enhanced growth and osteogenic differentiation of human osteoblast-like cells on boron-doped nanocrystalline diamond thin films.
abstract: Intrinsic nanocrystalline diamond (NCD) films have been proven to be promising substrates for the adhesion, growth and osteogenic differentiation of bone-derived cells. To understand the role of various degrees of doping (semiconducting to metallic-like), the NCD films were deposited on silicon substrates by a microwave plasma-enhanced CVD process and their boron doping was achieved by adding trimethylboron to the CH(4):H(2) gas mixture, the B∶C ratio was 133, 1000 and 6700 ppm. The room temperature electrical resistivity of the films decreased from >10 MΩ (undoped films) to 55 kΩ, 0.6 kΩ, and 0.3 kΩ (doped films with 133, 1000 and 6700 ppm of B, respectively). The increase in the number of human osteoblast-like MG 63 cells in 7-day-old cultures on NCD films was most apparent on the NCD films doped with 133 and 1000 ppm of B (153,000 ± 14,000 and 152,000 ± 10,000 cells/cm(2), respectively, compared to 113,000 ± 10,000 cells/cm(2) on undoped NCD films). As measured by ELISA per mg of total protein, the cells on NCD with 133 and 1000 ppm of B also contained the highest concentrations of collagen I and alkaline phosphatase, respectively. On the NCD films with 6700 ppm of B, the cells contained the highest concentration of focal adhesion protein vinculin, and the highest amount of collagen I was adsorbed. The concentration of osteocalcin also increased with increasing level of B doping. The cell viability on all tested NCD films was almost 100%. Measurements of the concentration of ICAM-1, i.e. an immunoglobuline adhesion molecule binding inflammatory cells, suggested that the cells on the NCD films did not undergo significant immune activation. Thus, the potential of NCD films for bone tissue regeneration can be further enhanced and tailored by B doping and that B doping up to metallic-like levels is not detrimental for cells.
authors.affiliation: Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
authors.forename: Lubica
authors.initials: L
authors.lastname: Grausova
authors.forename: Alexander
authors.initials: A
authors.lastname: Kromka
authors.forename: Zuzana
authors.initials: Z
authors.lastname: Burdikova
authors.forename: Adam
authors.initials: A
authors.lastname: Eckhardt
authors.forename: Bohuslav
authors.initials: B
authors.lastname: Rezek
authors.forename: Jiri
authors.initials: J
authors.lastname: Vacik
authors.forename: Ken
authors.initials: K
authors.lastname: Haenen
authors.forename: Vera
authors.initials: V
authors.lastname: Lisa
authors.forename: Lucie
authors.initials: L
authors.lastname: Bacakova
mesh_terms: D000327:Adsorption; D000818:Animals; D001895:Boron / Q000737:chemistry*; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D024042:Collagen Type I / Q000737:chemistry; D018130:Diamond / Q000737:chemistry / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D049329:Nanostructures / Q000737:chemistry*; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects* / Q000276:immunology; D010012:Osteogenesis / Q000187:drug effects*; D055585:Physical Phenomena; D012666:Semiconductors; D012825:Silicon / Q000737:chemistry
chemical_list: D024042:Collagen Type I; D018130:Diamond; D001895:Boron; D012825:Silicon