Micro-Pattern Guided Adhesion of Osteoblasts on Diamond Surfaces

Abstract

Microscopic chemical patterning of diamond surfaces by hydrogen and oxygen surface atoms is used for self-assembly of human osteoblastic cells into micro-arrays. The cell adhesion and assembly is further controlled by concentration of cells (2,500-10,000 cells/cm2) and fetal bovine serum (0-15%). The cells are characterized by fluorescence microscopy of actin fibers and nuclei. The serum protein adsorption is studied by atomic force microscopy (AFM). The cells are arranged selectively on O-terminated patterns into 30-200 μm wide arrays. Higher cell concentrations allow colonization of unfavorable H-terminated regions due to mutual cell communication. There is no cell selectivity without the proteins in the medium. Based on the AFM, the proteins are present on both H- and O-terminated surfaces. Pronounced differences in their thickness, surface roughness, morphology, and phase images indicate different conformation of the proteins and explain the cell selectivity.

Osteogenic cell differentiation on H-terminated and O-terminated nanocrystalline diamond films

“…Until now, biological studies on NCD films with tuned wettability have been predominantly focused on osteoblast adhesion and growth, 29 or on short-term osteogenic differentiation. 30,31 Some studies have also been focused on differentiation of neural stem cells, for which a hydrogenated NCD surface supports differentiation into neurons while an oxygenated NCD surface supports differentiation towards oligodendrocytes.…”

Nanocomposite and Nanostructured Carbon-based Films as Growth Substrates for Bone Cells

“…1) can be considered as the most advantageous material for advanced biomedical and biosensoric applications, which is mainly due to the absence of its cytotoxicity, immunogenicity and other adverse reactions (Schrand et al, 2007;Huang et al, 2008;Grausova et al, 2009a,b;Rezek et al, 2009; for a review, see Bacakova et al, 2008a). Other remarkable properties of nanodiamond, enabling its application in biotechnologies and medicine (particularly in hard tissue surgery), are high hardness, a low friction, and also high chemical, thermal and wear resistance.…”

Nanocrystalline Diamond Films: Applications and Advances in Nanomedicine

“…Hydrophobic H-terminated surfaces were found less favorable for osteoblastic cell adhesion, spreading and viability than hydrophilic O-terminated surfaces [5]. Recently, it was shown that microscopic (30-200 μm) patterns of H-and O-terminated surface can lead to a selective adhesion and arrangement of osteoblasts [85]. This effect also works on human periodontal ligament fibroblast and human cervical carcinoma (HeLa) cells [85][86][87].…”

“…It was proposed that the selectivity is due to the serum proteins, which are adsorbed in about the same monolayer thickness (2-4 nm) on both H and O-diamond surfaces, but in different composition and conformations of proteins [88]. When osteoblasts were placed on the diamond surface in McCoy's 5A medium without FBS, cell attachment on H/O-patterned diamond surfaces was not selective [85,89]. This excluded a direct effect of diamond C-H and C-O surface dipoles on the cell selectivity.…”

“…Recently, it was shown that microscopic (30-200 μm) patterns of H-and O-terminated surface can lead to a selective adhesion and arrangement of osteoblasts [85]. This effect also works on human periodontal ligament fibroblast and human cervical carcinoma (HeLa) cells [85][86][87]. The differential adsorption of "serum proteins" on the negative or positive charged regions from medium with fetal bovine serum (FBS) was studied.…”