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Currently, there is an interest in the development of flexible strain gauges that can be attached to human body for movements detection in postoperative period, during rehabilitation after injuries and strokes, etc. Such gauges usually consist of a polymer matrix and electrically conductive filler. In this work, manufacturing technology of strain-sensitive nanocomposite material consisting of biocompatible polymer (silicone) matrix and carbon nanotubes filler has been developed. Electrically conductive carbon nanotubes networks in non-conductive polymer matrix were obtained, high electrical conductivity of the material (∼0.1 S/m) was achieved. Network architecture was built using pulsed ytterbium laser, operating at wavelength 1064 nm. Production of two types of strain gauge elements with strain gage coefficient 4-6 using technology is shown. Developed technology opens up broad prospects for production of various biomedical strain gauges.

The effect of electrostimulation on the growth of fibroblasts and mesenchymal stem cells cultured on electrically conductive layers of a biopolymer composite were studied. Layers of a biopolymer composite based on carbon nanotubes, albumin, collagen, chitosan were formed by using infrared laser radiation. The developed system for electrostimulation provides the generation of electrical signals with specified electrical parameters; control and regulation of them; transmission of electrical signals to cells growth on layers of a biopolymer composite. The effect of electrostimulation on cell growth for 48 hours with 1 ms pulse duration, 1 s pause duration, amplitude ranged from 60 to 200 mV was investigated by optical, fluorescence, scanning electron microscopy, MTT test.

In this work, a method of the formation of cell and tissue-engineering structures for regeneration of heart and blood vessel tissues was developed. Structures consisted of carbon nanotubes and biopolymers: albumin, collagen and chitosan. The device for the formation of the structures was developed based on a pulsed ytterbium laser with a wavelength of 1064 nm. The fabrication of structures was carried out by layer-by-layer laser curing of liquid dispersions of components, while the electromagnetic field of the laser led to the formation of a nanotubes scaffold in the matrix. The surface relief of each of the layers made using the developed method was investigated with an atomic force microscope. The biocompatibility of the resulting constructs was studied in vitro during cultivation of endothelial cells, fibroblasts and cardiomyocytes. The results of using the formation method are promising for obtaining structures that support tissue regeneration of cardiovascular system.

This paper presents a method for creating three-dimensional networks of carbon nanotubes by welding nanotubes under laser radiation. To carry out nanowelding, single-walled carbon nanotubes were deposited on a SiO 2 substrate, after which they were irradiated with an ytterbium laser. Structural parameters and hardness characteristics of the samples were studied. Such 3D networks can act as electrically conductive nanoframes in biomaterials.

Method of electrical stimulation of cells on bioengineering nanocomposite substrates with electrical pulses with amplitude from 60 mV to 120 mV and pulse duration of 2.5 ms for 24 h is developed. Nanocomposite substrates consist of a polymer matrix based on natural components - protein albumin, aminosugar chitosan and reinforcing filler - carbon nanotubes have a three-dimensional structure with an internal electrically conductive frame created by laser formation. A developed device for electrical stimulation of cells allows the transmission of stimulating signals to cells through a conducting substrate consisted of bioengineer nanocomposite. As a result, the dependence of the proliferation factor on the electric signal amplitude was obtained and characteristics of the spreading of cells on the substrate was investigated.

An analytical review of the mechanical characteristics of cardiovascular structures based on collagen, chitosan and albumin with carbon nanotubes, obtained by using the laser system. Studying of two multiscale models of the interaction between the layers of a cell-engineering construction and the layers of heart tissue.

An analytical review of tissue-engineered implants for the cardiovascular system tissues regeneration was carried out. A comparison of laser methods for manufacturing cellular scaffolds was made. On the basis of theoretical studies, the possibility of creating a nanocarbon scaffold under the action of laser radiation has been proved. This scaffold is used to reinforce scaffolds based on protein matrix.

To print three-dimensional cellular- and tissue-engineered structures intended for implantation in the damaged area of cardiovascular system, it is necessary to know the nonlinear optical characteristics of using materials. Therefore, studies of the effect of pulsed nanosecond laser radiation on proteins such as bovine serum albumin (BSA), bovine collagen (BC), and single-walled carbon nanotubes (SWCNTs) were carried out. Experiments were carried out with the open-aperture z-scan method and fixed sample location method. Z-scan curve and input-output energy curve were obtained. Four samples of aqueous dispersions were used: 25 % BSA with water, 2 % BC with water and the same samples with SWCNTs. The linear transmission of the samples were determined by optical spectroscopy method. The limiting threshold, linear and nonlinear absorption coefficients were calculated for each dispersion. It was found that absorption of albumin and collagen dispersions with SWCNT increased sharply with the increase of the input radiation fluency.

The article presents the results of studies of nanocomposite biostrucrures based on a protein matrix, impregnated with carbon nanotubes (CNTs). To prepare the samples, aqueous dispersions of bovine serum albumin (BSA) and bovine collagen (BC), with the addition of two types of single-walled carbon nanotubes (SWCNT) were prepared. Nanocomposite materials were created by the method of layer-by-layer deposition and laser evaporation of the aqueous component from dispersions. As sources of laser radiation, a continuous diode laser with a wavelength of 810 nm, a power of 2 W, and a semiconductor laser with a wavelength of 810 nm were used. Infrared (IR) spectra and Raman spectra of biostructures were obtained and analyzed. The spectra of nanocomposite biostructures demonstrated a high degree of binding of the organic (protein) and inorganic (SWCNT) components. From Raman spectra, the structure and defectiveness of a carbon scaffold was studied.

In this study is shown the possibility of the Raman spectroscopy as a method to control the parameters of carbon nanotubes (CNTs) subjected to powerful ultrasonic impact. These parameters affect the strength of the nanoframe formed under the action of laser radiation, which ultimately affects the final strength of the nanocomposite. Also a linear dependence of the intensity of G-band (∼1590 cm−1) spectrum of the nanocomposite from the mass concentration of CNTs was found, which allows to determine the concentration of CNTs in the desired area of the film of the nanocomposite with an error of less than 5 %.

Composite nanocoating of synthetic fibers for implantable materials has been developed. The coating is intended to improve the adhesion and proliferation of biological cells, which can lead to a reduction in damaged tissue regeneration time after implantation of synthetic material in the human body. The basis of the coating is a dispersion of carbon nanotubes in the protein matrix. The coating was formed on the surface of synthetic fibers using ultrasonic waves and laser irradiation. Under the influence of the laser radiation electric field, there have been carried out evaporation of the water component of the dispersion and formation of the carbon nanotubes scaffold, which provides properties of the coating that promote cell attachment. The structure of coating was studied by atomic force microscopy. In vitro studies of interaction between nanocarbon coatings and biological cells of connective tissue were carried out. By scanning electron microscopy we showed the absence of the negative impact of carbon nanotubes on cell proliferation. Also toxicity studies of nanocoating have been conducted using white rat model. These studies showed no negative impact of synthetic fibers nanocoating on biological and morphological properties of the animal's tissues.

Composite biomaterial consists of bovine serum albumin 25 wt. % and single-walled carbon nanotubes