Protein Corona and Immune Responses of Borophene: A Comparison of Nanosheet-Plasma Interface with Graphene and Phosphorene.

Borophene has emerged as a type of two-dimensional monoelemental nanomaterials with excellent drug loading capacity and photothermal properties. Here, we demonstrated the adsorption of plasma proteins onto borophene nanosheets (B NSs) and the promoted immune responses of macrophage by the B NS-corona complex. We discovered that plasma proteins changed the surface identities of B NSs. Using proteomics analysis, 46.5% of the proteins bound to B NSs (94 plasma proteins) were immune-relevant proteins. Uptake of B NSs by phagolysosomes was observed, and the plasma corona promoted the uptake. In comparison with graphene and phosphorene, we found that 32 plasma proteins appeared on all of the three nanosheets. The proportion of immune-relevant proteins in graphene-corona and phosphorene-corona was 41.3% and 75.6%, respectively. The components of the adsorbed immune-relevant proteins show diversity, which influence the immune responses of these nanosheets. Phosphorene-corona showed the most remarkable immunoregulatory behavior in these nanosheets. For the first time, we compared the highly complex protein corona at the nanosheet-plasma interface of three key 2D monoelemental nanosheets. Our study helps to understand the interaction between borophene and biological systems and provides a theoretical basis for the development and application of borophene in the biomedical field.