Influence of laser radiation on carbon nanotubes for the formation of frame materials in bioelectronics

Abstract

Single-walled carbon nanotubes (SWCNT) nanoframes have been created in the form of structured films on a silicon substrate as well as in the bulk of biopolymers of albumin, collagen, and chitosan. Biopolymers were required to create multilayer, electrically conductive bioelectronic structures for reconstructing the layers of the heart. For this, a laser setup was used based on a pulsed fiber ytterbium laser with a wavelength of 1064 nm and a scanning system. Liquid dispersions of SWCNT in ethanol and aqueous dispersions of biopolymers were applied onto a substrate by layer spraying. Then they were irradiated with laser radiation. The effect of the binding of SWCNTs and their bundles to each other under the action of laser radiation on a silicon substrate is demonstrated. Using SEM and TEM, the formation of “T”, “X” and “Y” shaped joints in films is demonstrated. The mechanical characteristics of structured films by laser have improved. The hardness of films with nanoframe after laser exposure increases more than 6 times compared to the original SWCNT film. The specific electrical conductivity of films with nanoframe after laser exposure increases more than 7 times. The specific electrical conductivity of nanoframe in biopolymer matrices varies in the range 0.6 - 12.4 S/m, depending on the type of biopolymer. These values exceed electrical conductivity of heart myocardium. The highest roughness is shown for the lower layer of chitosan and SWCNT, and the smallest for the upper layer of albumin and SWCNT of the bioelectronic structure. Using confocal microscopy, the possibility of the formation of a cellular structure under the action of laser radiation on an aqueous biopolymer dispersion of SWCNT has been demonstrated. The cellular structure, electrical conductivity and nanoframe from SWCNT promoted better vital functions of heart cells - cardiomyocytes.