Interaction of laser radiation with carbon nanotubes for the creation of biocompatible media

The paper describes the process of carbon nanotubes structuring as a result of their interaction with laser radiation. Mechanisms of the formation of biocompatible media with single-walled carbon nanotubes (SWCNTs) under the action of laser radiation were proposed. An investigation of the temperature field distribution in the defect region of two nanotubes contact after laser heating showed that the defect region had a temperature of ∼ 50 % higher than the temperature of the defect-free regions of the structure. The formation of four covalent C-C bonds occurred in 2-2.5 ps at an effective binding distance of SWCNTs 3-5 A. The interaction energy of the tubes ranged from -7.43 to -7.36 eV/atom at the formation of bonds between SWCNTs. The distribution of the maximum values of the electromagnetic field over the SWCNTs volume was in good correlation with the SEM images of the branched nanoscaffold in the protein matrix. The scaffold provided a hardness of biocompatible media up to 400 MPa. Topography study of the media surface led to the conclusion that an increase of SWCNTs concentration helps to reduce the number of pores and increase their size. Created biocompatible media can be used as tissue-engineered matrixes that promote cell proliferation. (paper)