Dependence of physical-chemical properties of fluorescent hybrid polymer carriers on the conditions of hydrothermal synthesis

Abstract

Currently, the search for new types of carriers for low-molecular weight substances, as well as the development of optimal methods for the eff ective encapsulation of these substances are important tasks of modern chemistry and pharmacology. However, there are still limitations in this area, among which one of the most signifi cant is the lack of the optimal carrier capable of stably retaining a low-molecular weight substance. The work presents hybrid polymer structures obtained by in situ hydrothermal synthesis as an eff ective candidate for these purposes. The fl uorescent dye rhodamine B has been used as a model low-molecular weight substance for encapsulation into the structures. The resulting hybrid polymer structures demonstrated good stability when stored in an aqueous environment for 336 h with the release of the low-molecular weight dye rhodamine B no more than 2%. In addition, the infl uence of the conditions for obtaining hybrid carriers (including the composition of the carriers (thickness of the polymer shell and the presence of a calcium carbonate core) and synthesis temperature) on their physical-chemical characteristics has been studied. Thus, the optimal approach for obtaining fl uorescent hybrid polymer carriers with a set of desired properties has been revealed. In particular, it has been shown that the optimal production conditions are hydrothermal synthesis temperature of 180 °C and the absence of CaCO3 core inside the polyelectrolyte shell which allow us to obtain a stable hybrid polymer carrier with bright fl uorescence. The results presented in this study can be used to create functional platforms and systems with tunable fl uorescent properties and the ability to deliver low-molecular weight substances.

Keywords

• hydrothermal synthesis
• low-molecular-weight dyes
• encapsulation
• core-shell structures
• release kinetics