## 3 Results and Discussion
### Electrical Conductivity of Nanocomposites  
The study of electrical conductivity made it possible to determine the features of the nanocomposites structure, namely the formation of branched 3D networks from SWCNT in the protein matrix. It is known that SWCNT under the action of laser radiation in a dielectric matrix (proteins) creates electrically conductive 3D networks with percolation nodes [47]. 3D networks of nanotubes are formed due to the formation of covalent bonds in defective regions of nanotubes that are in close proximity.  
Figure 6 shows the conductivity data for nanocomposites with different compositions. The diagram shows that an increase in the SWCNT concentration from 0.001 to 0.01 wt.% leads to an increase in the specific electrical conductivity of nanocomposites from 1.1 \(\pm\) 0.05 to 3.2 \(\pm\) 0.1 S/m. The increase in electrical conductivity depends on an increase in the number of X- and Y-shaped percolation nodes. Consequently, higher concentration of nanotubes increases the probability of binding of defective nanotubes regions located at a distance of 1.38 to 1.55 A from each other. In this regard, Figure 6 shows regularity in the excess of electrical conductivity in nanocomposites with SWCNT2 compared to nanocomposites with SWCNT1. From the analysis of the Raman spectra, it was found that the defectiveness in the nanocomposites with SWCNT1 is higher than in the samples with SWCNT2. Most likely, this is due to the fact that the defective regions of SWCNT1 formed chemical bonds to a greater extent with protein molecules in nanocomposites than with each other. While in nanocomposites with branched 3D networks of SWCNT2, their defectiveness is much lower. Most likely, SWCNT2 formed covalent bonds with each other, increasing the electrical conductivity of nanocomposites to 3.2 \(\pm\) 0.3 and 4.3 \(\pm\) 0.2 S/m for 0.001 and 0.01 wt.%, respectively. However, the lower stability of SWCNT2 in a water-protein dispersion led to a larger error in measuring the electrical conductivity compared to nanocomposites based on more stable and homogeneous dispersion with SWCNT1. It is known that the electrical conductivity of the native myocardium varies in the range of 0.03-0.6 S/m [56]. Therefore, the implantable part of the device for electrical stimulation of the myocardium or restoration of its structure must have comparable or higher electrical  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Type and Concentration of** & & & \\
**Nanotubes in** & **Specific Surface (m2/g)** & **Specific Volume of** & **Mesopores (mL/g)** & **Mesopore Size Ranges (nm)** \\ \hline SWCNT1 (0.001 wt.\%) & 8.4 \(\pm\) 0.2 & 1.8 \(\pm\) 0.1 & 30–50 \\  & & & 50–100 \\ \hline SWCNT1 (0.01 wt.\%) & 6.7 \(\pm\) 0.2 & 1.5 \(\pm\) 0.1 & 10–20 45–70 \\ \hline SWCNT2 (0.001 wt.\%) & 6.9 \(\pm\) 0.3 & 1.6 \(\pm\) 0.2 & 85–100 \\ \hline SWCNT2 (0.01 wt.\%) & 3.8 \(\pm\) 0.3 & 0.9 \(\pm\) 0.2 & 38–55 95–100 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Specific surface area, specific volume and pore size distribution in nanocomposites.  
conductivity values. Thus, nanocomposites created from both types of SWCNT with both concentrations are suitable for such a task.