3, Boise State University, Boise, Idaho, United States
2, Istituto Italiano di Tecnologia, Pisa, , Italy
The intersection of graphene and biology has emerged as a promising area where graphene’s physical properties may help elucidate fundamental insights into the chemistry of life. However, graphene’s structure and properties are tightly coupled to synthesis and processing conditions,  thus influencing biomolecular interactions at graphene – cell interfaces. For example, graphene can be obtained via micromechanical cleavage and liquid assisted exfoliation of bulk graphite, Chemical Vapor Deposition (CVD) on transition metal foils, and epitaxial growth on SiC. Such processing conditions can impact crystal size, the density of structural defects, and chemical, thermal, and electrical properties. In this study, we grew C2C12 cells, a pluripotent (mouse muscle) cell line, on graphene bioscaffolds with varying structure – property – processing – performance (SP3) correlations. We find that such SP3 correlations significantly influence C2C12 differentiation, myotube formation, and gene expression, suggesting that the cell – graphene interface can be engineered to control biomolecule structure and function in adherent cells.
Similar to our previous work, cells were seeded on glass (control), CVD graphene, printed graphene of increasing pass numbers (2 to 10 passes), and epitaxial graphene on SiC. Cells were maintained for one week in culture. Gene expression patterns were analyzed by quantitative RT-PCR. Cell morphology and viability was assessed by cytochemistry. Differentiation was assessed by immunocytochemistry using an antibody specific for Troponin I. Samples were counterstained with phalloidin to identify actin and DAPI to identify the nuclei. Biocompatibility was determined by measuring cellular viability.
Our results indicate that the manner in which the graphene is produced and the surface and structural properties of the resulting bioscaffolds correlate to differential expression patterns of molecular markers for differentiation of pluripotent cells. Successful cellular attachment and persistent cellular viability may also vary depending on the surface characteristics of the graphene.
In conclusion, our results highlight the first study of graphene bioscaffold SP3 characteristics on biomolecular structure and function of adherent pluripotent cells, highlighting a novel tool for engineering tissue function on graphene surfaces.