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In this paper, the hydrodynamic size and zeta potential of various polymer spherical particles (70-350 nm) were measured. The measurements were carried out using the methods of dynamic light scattering (DLS) and electrophoretic light scattering (ELS). It was shown that the values of zeta-potential of 70-180 nm particles undergo changes of 10-20 % of the initial values during two years. However, the aggregation of some sample was observed during storage or ultrasonic treatment which could be explained by surface charge density undergoing transformation upon storage. Water, ethanol, propanol, glycerin were used for the preparation of the dispersion media, and the effect of medium with different viscosities on size distribution analysis was evaluated. Not quite accurate reference data of the dispersion media introduces the size measurement errors of about 18 %, which, however, acceptable for rough and quick estimation of particle sizes at different stages of preparation and transformation.

The change in the dimensions of the aggregates of the laser solders components during their heating and subsequent denaturation has been investigated. It has been revealed that only the bovine serum albumin aggregates with a hydrodynamic radius of 4.1 ± 0.7 nm are subject to denaturation, and the aggregates of multiwalled carbon nanotubes do not affect denaturation.

The experimental setup for multispectral nanoparticle tracking analysis is developed. The optical system for sample illumination in nanoparticle tracking analysis is designed that makes it possible to obtain images of particles in suspensions with a high signal-to-noise ratio. The results of the comparison of particle size distributions obtained by nanoparticle tracking analysis using developed experimental setup, dynamic light scattering method and scanning electron microscope are shown.

The experimental setup for determination of particle sizes by nanotracking is developed. It is shown the possibility to identify particles with different fluorescent labels using developed experimental setup. The first results of analysis for samples of polystyrene micro- and nanoparticles are obtained using developed experimental setup.

Samples of aqueous dispersions of bovine serum albumin with different acid-base value pH were studied using dynamic light scattering and electrophoretic light scattering methods. The hydrodynamic diameter of monomers, small aggregates and large aggregates of albumin and the zeta potential of the samples were measured. Dependencies of the hydrodynamic diameter and the zeta potential of albumin aggregates on the protein concentration in solution and pH of the aqueous dispersion of albumin were obtained.

Increase the weld strength is main directions of development of laser welding technology. Laser solders are used to increase tensile strength of welds and reduce of tissue temperature necrosis. Soldering components interaction effect the solder tensile strength characteristics of laser welds. Tensile strengths for welds obtained using of solder various concentration BSA and SWCNT was measured. Dimensions laser solder aggregates were measured. The dependence between the dimensions of the aggregates of laser solder and the tensile strength of the weld has been revealed.

Studies were performed on the interaction of laser solder components (bovine serum albumin and single-walled carbon nanotubes) by laser light scattering method. The formed aggregates size depends on the ratio of the albumin concentration to nanotubes concentration.