Exploring the biotoxicity of carbon boride nanosheets (BC3) based on the villin headpiece protein model

The recently synthesized single-layer carbon boride (BC3), has been explored for biomedical applications. However, the interaction between BC3 and biomolecules needs to be further explored to evaluate its potential toxicity to biological systems. Here, using the villin headpiece (HP35) as a representative protein model, the binding behavior of proteins to BC3 and the structure evolution of proteins were studied by molecular dynamics simulation. Our data revealed that HP35 can quickly load and form stable binding to BC3 surface. The BC3 caused moderate destruction of the HP35 by destroying its native hydrogen bonds and unwinding its helices. The BC3/HP35 interaction strength is linearly correlated with the contact number between BC3 and HP35. HP35 forms binds to BC3 mainly through van der Waals interactions and pi-pi stacking. Compared to graphene, the polarized nature of BC3 can slightly strengthen the binding between BC3 and HP35. BC3 still faces the problem of potential cytotoxicity to biological system. These findings shed light on the biological effects of BC3 at the molecular level and guide the future application of BC3-based devices in biomedicine.