Macro-, Micro- and Nano-Roughness of Carbon-Based Interface with the Living Cells: Towards a Versatile Bio-Sensing Platform

• Main Authors: Lena Golubewa, Hamza Rehman, Tatsiana Kulahava, Renata Karpicz, Marian Baah, Tommy Kaplas, Ali Shah, Sergei Malykhin, Alexander Obraztsov, Danielis Rutkauskas, Marija Jankunec, Ieva Matulaitienė, Algirdas Selskis, Andrei Denisov, Yuri Svirko, Polina Kuzhir
• Format: Article
• Language: English
• Published: MDPI AG 2020-09-01
• Series: Sensors
• Subjects: pyrolytic carbon; graphene; graphene nanowalls; black silicon; glioma cells; biocompatibility
• Online Access: https://www.mdpi.com/1424-8220/20/18/5028

Integration of living cells with nonbiological surfaces (substrates) of sensors, scaffolds, and implants implies severe restrictions on the interface quality and properties, which broadly cover all elements of the interaction between the living and artificial systems (materials, surface modifications, drug-eluting coatings, etc.). Substrate materials must support cellular viability, preserve sterility, and at the same time allow real-time analysis and control of cellular activity. We have compared new substrates based on graphene and pyrolytic carbon (PyC) for the cultivation of living cells. These are PyC films of nanometer thickness deposited on SiO₂ and black silicon and graphene nanowall films composed of graphene flakes oriented perpendicular to the Si substrate. The structure, morphology, and interface properties of these substrates are analyzed in terms of their biocompatibility. The PyC demonstrates interface biocompatibility, promising for controlling cell proliferation and directional intercellular contact formation while as-grown graphene walls possess high hydrophobicity and poor biocompatibility. By performing experiments with C6 glioma cells we discovered that PyC is a cell-friendly coating that can be used without poly-<span style="font-variant: small-caps;">l</span>-lysine or other biopolymers for controlling cell adhesion. Thus, the opportunity to easily control the physical/chemical properties and nanotopography makes the PyC films a perfect candidate for the development of biosensors and 3D bioscaffolds.