ИСТИНА

It has been shown that biodegradable and biocompatible polylactide (PLA) is one of the most perspective polymers for production of eco-friendly packaging, disposables and a great variety of biomedical products [1]. Stereochemical structure of PLA can be easily modified via control of L- and D-lactide content leading to either amorphous or semi-crystalline material [2]. Block copolymers based on PLA are of special interest. Amphiphilic block copolymers attracted increased attention for decades due to their ability to self-assemble, segregate, and form highly organized structures in solution, on surface, and in bulk [3]. These structures can serve as templates for control of inorganic nanoparticle formation or lead to well-defined hybrid superstructures. Formation of self-assembled nanostructures (micelles) in selective solvents, and in particular in aqueous media, is of special interest due to their possible biomedical applications [4]. Structural variability of the block copolymers in solution is a convenient platform to create materials with well-defined properties. Thus, the understanding of the solution behavior of block copolymers is crucial for control over the structure and properties of the resultant materials. In the present work small-angle X-ray scattering was used for detailed structural characterization of nanoparticles formed in solution by PLA-based di- and tri-block copolymers. Obtained scattering data have been analyzed by advanced methods of SAXS data interpretation and modeling to design 3D structural models of the di- and tri-block copolymers. Additionally, analysis of the block copolymers capacity to absorb and release bioactive substances allowed us to evaluate the prospects of usage of the block copolymers as drug delivery systems. References [1] Hartmann MH. Biopolymers from renewable resources. In: Kaplan D.L., editor. Biopolym. from Renew. Resour. Berlin,.Heidelberg: Springer Berlin Heidelberg; 1998. p. 367–411. [2] Bordes P, Pollet E, Averous L. Nano-biocomposites: biodegradable polyester/nanoclay systems. Prog Polym Sci 2009;34:125–55. [3] Hamley, I. W., Nanostructure fabrication using block copolymers. Nanotechnology, 2003, 14, R39–R54. [4] Foerster, S.; Plantenberg, T., From self-organizing polymers to nanohybrid and biomaterials. Angew. Chim. Int. Ed., 2002, 41, 688–714. This work was supported by Russian Foundation for Basic Researches, project 16-03-00375