Viability and proliferation of A549 cell line on the surface of micro-, nano- and ultrananocrystalline diamond films grown by HFCVD with tailored gases

This article describes key material science/technology issues to implement polycrystalline diamond scaffolds to enable processes for biological cells growth relevant for using cells grown in the laboratory for the treatment of human biological conditions. Issues investigated include 1. Synthesis/characterization of microcrystalline diamond (MCD), nanocrystalline diamond (NCD) and transformational ultrananocrystalline diamond (UNCD) coating-based scaffolds. Diamond films were grown on silicon substrates using the hot filament chemical vapor deposition (HFCVD) technique, by which filaments heated to ∼2,300 °C induce cracking of CH 4 molecules into C atoms/CHx (x = 1, 2, 3) radicals, growing diamond films via chemical reaction on the substrates' surface. MCD and NCD + films were grown flowing the H 2 /CH 4 gas mixture. NCD- and UNCD films were grown using the Ar/CH 4 gas mixture plus H 2 flux (73.5%, 49%, and 9.8%), which for high fluxes, induced increased the concentration of H-containing trans-polyacetylene (T-PA) molecules in UNCD films' grain boundaries, impacting biological performance. 2. Studies of viability and proliferation of human lung carcinoma cell line (A549) grown on surfaces of MCD, NCD, and UNCD films, using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, which showed no significant difference in cell proliferation among the MCD, NCD, and UNCD films.