GC-01. Development of methods for modifying nano- and microcarriers for in vitro and in vivo imaging
Darya R. Akhmetova1, Timofey E. Karpov1, Alisa S. Postovalova1, Albert R. Muslimov2, Alexander S. Timin1, Mikhail V. Zyuzin3
1 Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia
2 Pavlov University, St. Petersburg, Russia
3 St. Petersburg National Research University of Information Technologies, Mechanics and Optics, St. Petersburg, Russia
Darya R. Akhmetova, phone: +7 (912) 691-35-90, e-mail: firstname.lastname@example.org
Nanoparticles have many advantages when used for various types of imaging. This type of drug carriers offers a wide range of material choices and are easily subject to various types of surface modifications. That is why there is currently a great deal of interest in this area and many organic and inorganic nanosystems have been developed that provide imaging signal, directionality and correction of the pharmacokinetics of particles. Despite a wide range of studies on combinations of various types of nanoparticles with fluorescent dyes and their widespread use in many types of research, the need of using new technologies and the appearance of particles that are more complex in their structure impose limitations on the already developed working protocols. Purpose of this project is to develop methods for modifying nano- and microcarriers with fluorescent dyes for in vitro and in vivo visualization.
Materials and methods
Particles of micron and submicron sizes were investigated in this work. To obtain studied carriers, CaCO3 cores were used for polymer microparticles with a Polyarginine/Dextran sulfate shell and SiO2 cores with a TiO2 metal shell as nanoparticles were used as a matrix of the multilayer structure. The modification was performed by the method of layer-by-layer deposition of polyelectrolytes; the adsorption of the layers was proved by measuring the change in ζ-potentials. To optimize fluorescence imaging techniques, the optical properties of Cyanine5, Cyanine7, and Rhodamine 800 dyes were investigated. To modify particles with fluorescent agents, these dyes were incorporated into the structure of carriers at the stage of matrix formation of nano- and microparticles. The efficiency of the developed protocols for labeling carriers with fluorescent agents was tested using confocal scanning laser microscopy (CLSM) and bioluminescence studies.
According to the results of the analysis by the СSLM methods and bioluminescence studies, it was proved that the developed protocols for fluorescent labeling of nano- and microcarriers demonstrated their effectiveness in preventing the release of the fluorescent label from the structure of the carriers. Experimental data have shown that the Cyanine5 fluorescent label is the most effective due to its high radiation intensity and long-term retention of fluorescent properties.
According to the results of the study, methods for modifying nano- and imicroparticles with fluorescent agents for in vitro and in vivo visualization were obtained and experimentally tested.
The work was done with the support of the Federal State Budgetary Institution “V. A. Almazov National Medical Research Center” of the Ministry of Health of the Russian Federation.
Nanobiotechnologies, polymeric microparticles, silica nanoparticles, modification, fluorescent visualization.