Successful formation of electronic interfaces between living cells and electronic components requires both good cell viability and performance level. This paper presents a technology for the formation of nanostructured arrays of multi-walled carbon nanotubes (MWCNT) in biopolymer (albumin) layer for higher biocompatibility. The layer of liquid albumin dispersion was sprayed on synthesized MWCNT arrays by deposition system. These nanostructures were engineered using the nanosecond pulsed laser radiation mapping in the near-IR spectral range (λ = 1064 nm). It was determined that the energy density of 0.015 J/cm² provided a sufficient structuring of MWCNT. The structuring effect occurred during the formation of C–C bonds simultaneously with the formation of a cellular structure of nanotubes in the albumin matrix. It led to a decrease in the nanotube defectiveness, which was observed during the Raman spectroscopy. In addition, laser structuring led to a more than twofold increase in the electrical conductivity of MWCNT arrays with albumin (215.8 ± 10 S/m). Successful electric stimulation of cells on the interfaces with the system based on a culture plate was performed, resulting in the enhanced cell proliferation. Overall, the MWCNT laser-structured arrays with biopolymers might be a promising material for extended biomedical applications.

A laser technology for creating nanocomposites from alternating layers of albumin/collagen proteins with two types of single-walled carbon nanotubes (SWCNT) at concentrations of 0.001 and 0.01 wt.% was proposed. For this purpose, a setup with a diode laser (810 nm) and feedback system for controlling the temperature of the area affected by the radiation was developed. Raman spectroscopy was used to determine a decrease in the defectiveness of SWCNT with an increase in their concentration in the nanocomposite due to the formation of branched 3D networks with covalent bonds between nanotubes. It was revealed that adhesion of proteins to branched 3D networks from SWCNT occurred. The specific electrical conductivity of nanocomposites based on large SWCNT nanotubes was 3.2 and 4.3 S/m compared to that for nanocomposites based on small SWCNT with the same concentrations—1.1 and 1.8 S/m. An increase in the concentration and size of nanotubes provides higher porosity of nanocomposites. For small SWCNT-based nanocomposites, a significant number of mesopores up to 50 nm in size and the largest specific surface area and specific pore volume were found. Nanocomposites with small SWCNT (0.001 wt.%) provided the best cardiac fibroblast viability. Such technology can be potentially used to create bioelectronic components or scaffolds for heart tissue engineering.

Currently, tissue engineering technologies are promising for the restoration of damaged organs and tissues. For regeneration of electrically conductive tissues or neural interfaces, it is necessary to provide electrical conductivity for the transmission of electrophysiological signals. The developed biocomposite structures presented in this article possess such properties. Their composition includes bovine serum albumin (BSA), gelatin, eosin-Y and single-walled carbon nanotubes (SWCNTs). For the first time, a biocomposite structure was formed from the proposed hydrogel using a nanosecond laser, and a two-photon absorption cross section value of 580 GM was achieved. Increased viscosity over 3 mPa∙s and self-focusing with a nonlinear refractive index of 42 × 10⁻¹² cm²/W make it possible to create a biocomposite structure over the entire specified area. The obtained electrical conductivity value was 19 mS∙cm⁻¹, due to the formation of effective electrically conductive networks. For a biocomposite with a concentration of gelatin 3 wt. %, formed by low-energy near-IR pulses, the survival of Neuro 2A nerve tissue cells was confirmed. The obtained results are important for the creation of new tissue engineering structures and neural interfaces from a biopolymer hydrogel based on the organic dye eosin-Y and carbon nanotubes by two-photon polymerization.

The aim of the work was to determine the viability, proliferative potential and adhesive properties of fibroblasts seeded on the surface and in the volume of a biocomposite formed using laser radiation and solders in in vitro experiments. Materials and methods. For the study, Wistar rat fibroblasts obtained at the National Research Center of Epidemiology and Microbiology named after Honorary Academician N.F. Gamalei were used. The biocomposite was formed using laser radiation and solders. The viability of cells on the surface of the biocomposite was assessed using the multiparametric RTCA iCELLigence cell culture analysis system (USA). The cytotoxicity of the biocomposite was determined in combination with triphenyltetrazolium bromide (MTT test, Merck Sigma-Aldrich, Switzerland). The proliferative potential and adhesive properties of fibroblasts were studied using a FEI Helios NanoLab 650 scanning electron microscope. Results and conclusions. The viability of cells on the surface and in the volume of a biocomposite formed using laser radiation and solder was proved using an electrophysical system for analyzing cell cultures. The absence of cytotoxicity of the biocomposite under the action of triphenyltetrazolium bromide in the spectrophotometric MTT test was demonstrated. It was found that during incubation of rat fibroblasts in the volume of the biocomposite, cell death is not observed, but, on the contrary, their proliferative potential is stimulated by increasing adhesion, which contributes to the formation of a dense cell layer. Conclusions. Biocomposite as a whole, as well as its individual elements, creates a favorable environment for the growth of fibroblast culture and can be used to restore the integrity of blood vessels using laser radiation and solder.