Influence of structure and composition of diamond-like nanocomposite coatings on cell viability

This paper investigates the influence of the structure and properties of diamondlike nanocomposite (DLN or a-C:H:SiOx) coatings synthesized by plasma-assisted chemical vapor deposition on cell viability and coating biocompatibility. The structure and properties of the DLN coatings are changed by the negative pulse amplitude of the bipolar bias voltage of the substrate. The structure of the obtained DLN coatings is studied by Fourier-transform infrared spectroscopy and Raman spectroscopy. Atomic force microscopy provides angstrom-level surface-profiling information. The microhardness testing of the DLN coatings is performed on a nanohardness indenter of a three-sided Berkovich pyramid. It is shown that the higher roughness of the substrate surface, the growth in the crystalline graphite content in the coating, and Si—C bonds improve the DLN coating biocompatibility deposited at a −500 V bias voltage and the cell viability (>98% of HeLa cells), resulting in a lower cell death (1–2%). It is demonstrated that DLN coatings can be applied in biomedicine.