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The article presents the results of the creation of composite materials. Laser irradiation in the near infrared region (970 nm) of water-albumin dispersion of single-layer carbon nanotubes (SLCNT) is characterised by an intensive absorption of radiation, which is accompanied by nanotube heating. Signifi cant warming occurs at the ends of nanotubes and in the areas of localised defects where the thermal conductivity is signifi cantly reduced. In terms of chemical reaction, the open ends of nanotubes and areas with defects appear to be most active, thus, the idea of splicing SLCNT in the defective areas was taken as the basis. Numerical simulation showed that the process of nanotube matching in the frame starts when the laser heats to a temperature of 80–100 oC. This process occurs within a few nanoseconds. The graphs of enthalpy allow us to conclude that the process of SLCNT frame forming with four defects in the form 1V (single carbon atom vacancies) present it the region of the tube junctions results in the greatest energetic advantage. In composite materials, the bonding of SLCNT with albumin molecules occurs though the Glu and Asp amino acid residues. The interaction energy between the nanotube frame and the albumin matrixis up to 580 kJ/mol. Molecular dynamic simulations show that an increase in the number of oxygen atoms leads to a decrease in the interaction energy between SLCNT and albumin. The attachment of the oxygen atoms to the SLCNT leads to the distortion of nanotubes, which increases with the increase in the number of oxygen atoms. The change of the attachment points of the oxygen atom to the nanotube oxygen atoms allows confi guring the desired shape of the nanotube frame in the albumin matrix. Composite materials based on SLCNT water-albumin dispersion have a developed surface with periodic peaks and troughs. This can be seen from the atomic force microscopy images and is associated with the carbon nanotube framework which is formed under laser radiation. The pore size ranges between 30-120 nm. Composite materials can provide superior adhesion of cells planted on their surface. It can be used as a tissue-engineered matrix to restore three-dimensional structure of bone and connective tissue.

A computational modeling is employed for quantitative assessment of weld formation and area of tissue temperature necrosis during the human skin laser soldering. The evaluation is carried out depending on the components composition of using solders, including bovine serum albumin (BSA), indocyanine green (ICG), and carbon nanotubes (CNTs), as well as the angle of incidence of laser light and its pulse duration. The influence of CNT on the change of thermodynamic characteristics of albumin denaturation and the rate of formation of the laser weld is investigated. The obtained results suggest to limit the duration of laser light pulse by temperature relaxation time to minimize transfer of thermal energy to reduce the heating of human skin tissues. The developed model has a great potential for further optimization of laser soldering of biological tissues technology with greater efficiency in minimizing the weld area. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]