The mechanisms of cellular growth has attracted scientists’ attention for a long time [Kenry, Lee, Loh, Lim. Biomaterials, 155, 236-250, (2018)]. In the quest to understand how this complex biological process occurs, recent investigations have focused on artificial growth of stem cells atop of inorganic surfaces such as graphene. It became apparent that certain proteins are likely responsible for holding cells on top of graphene surfaces, fibronectin being one of them.
In a pilot study [Frahs et al., ACS Appl. Mater. Interfaces, 11, 41906-41924 2019] we study the adhesion of fibronectin to graphene through simulations as pictured in Figure 1.
The investigation is made to show that fibronectin has a binding affinity to graphene, which in the long run could indicate that cell growth outside the human body is possible, which in turn would lead to huge applications in biomedicine.
The study found evidence both experimentally as well as computationally that the adhesion of fibronectin to graphene was possible and found that arginines were especially important in the process of binding the fibronectin to the graphene surface.
The difference in contributions from different amino acids started another study [Frederiksen, Solov'yov Eur. Phys. J. D (2020) 74: 44], in which 18 of the same amino acid was deposited on the graphene sheets used in the earlier study. This was repeated 20 times, one time for each amino acid, and about what amino acids could contribute to binding of proteins.
Having 18 of the same amino acid ensured that the statistics of the study were sturdy, see Fig. 2, and that more than one binding mode were found for several of the amino acids, whereas having only one might not have revealed this.
The calculation were redone for the same system but with the amino acids in vacuum and using the drude polarizable model [Jiang et al. J Phys Chem Lett. 2011; 2(2)]. Lastly the system was downscaled such that a QC calculation could be done on a hexagonal piece of graphene with an amino acid on top.