Sub-nanometer-sized carbon nanoparticle shows higher biocompatibility to DNA than nanometer-sized nanoparticles

Abstract Nanomaterials have been extensively studied for their potential applications in biomedical research, but the concerns of nanotoxicity still remain. A systematic understanding of how the geometrical factors of nanomaterials, especially the dimensional size, regulating the toxicity is critical for the development of biomedical materials, which has yet to be documented. In this work, we have studied how the ultra-small-sized C 28 nanoparticles bind to and regulate the structure of double stranded (dsDNA) by molecular dynamics simulations. Our results show that the C 28 molecule can strongly bind to the nucleic acid terminal or the minor groove. It is interesting to observe a high sequence preference for C 28 binding which prefers to bind to GC-rich than AT-rich segments. The C 28 binding does not cause evident structural distortion and has little effect on the global motion of dsDNA, showing relatively higher biocompatibility than most reported nanomaterials that are usually at the nanometer size. These results reveal a fact that the nanomaterials toxicity is highly correlated to their size where sub-nanometer sized materials may have higher biocompatibility. This could provide deep understanding of how to control the biomaterials effects and might further extend applications of nanomaterials in biomedical research.