Supramolecular Polymer Systems
Profile of the Department
The general focus of the Department is to study and exploit self-association processes and supramolecular structures in polymer systems in solutions, dispersions and bulk. This area of research exploits knowledge of physical chemistry and experimental physics, extensive chemical and synthetic background, and practical aspects of polymer self-association. Special attention is paid to processes of complexation, formation of polymer micelles, nanocapsules and gels. Self-association processes and the resulting structures are investigated on microscopic, mesoscopic and macroscopic levels. Applications of biocompatible and biodegradable self-associated systems for biomedical use are being developed, including radioactively labeled polymers for diagnosis and therapy. The general aim is mastering the process of self-organization in polymers and copolymers leading to nanostructured materials for nanotechnology and biomedical applications. The interdisciplinary research of the Department is reflected by the composition of the team that includes physicists, specialists in organic and polymer synthesis, in physical chemistry and radiochemistry.
Research
Four research areas are supported as the Department’s key directions:
- Development of synthetic procedures for the preparation of functional polymers with desired properties.
- Investigation of the internal structure of self-assembled polymer systems with scattering and imaging techniques.
- Synthesis of polymers and design of new nanostructured materials, their characterization by instrumental physico-chemical methods and, where relevant, supported with radiochemical studies.
- Exploitation of external stimuli-triggered polymer self-assembly and disassembly as the core activity of the Department. The systems are responsive to external stimuli, in particular to changes in temperature, pH, presence of reactive oxygen species and intracellular enzymes.
Research Activities
SELF ASSEMBLED TRIPHILIC SYSTEMS
The self-assembly of supramolecular polymer systems brings extraordinary benefits to various applications. Very interesting from the self-assembly point of view are such triblock copolymers, where different nature of the three blocks may bring structural features to the nanoassemblies not achievable by other means. Triphilic polymers have hydrophilic, hydrophobic and perfluorinated blocks which are immiscible with each other and are highly application-relevant. We focused on triphilic poly(2-oxazoline) triblock copolymers with high fluorine content toward our future aim of developing 19F magnetic resonance imaging (MRI) contrast agents for the purpose of medicinal diagnostic noninvasive imaging. It has been already shown that these polymers have high potential for future development of MRI contrast agents. An easier approach is to use commercially available perfluoroalkyl precursors as perfluorinated ”blocks“. With such approach, the structures and shapes of the nanostructures are controlled by the length of the perfluoroalkyl chain. Single-layer and multi-layer vesicles as well as rod-like micelles were prepared in aqueous solutions.
CONCEPTUALLY NEW IMMUNORADIOTHERAPY BASED ON THERMORESPONSIVE POLYMERS
We develop conceptually new immunoradiotherapy polymer systems for treatment of cancerous diseases. Our polymers are based on natural polymer β-glucan copolymerized with carefully designed thermoresponsive polyoxazolines bearing moieties to bind medicinal therapeutic radioisotope yttrium-90. Such polymer is soluble below body temperature of 37 °C but creates a self-assembled brachytherapy depot immediately after injection into the cancerous tissue, where the radioisotope starts to damage cancer cells. Simultaneously, the polymer stimulates an extensive immune activation reaction at the site of injection. The polymer system itself exhibits no toxicity, moreover it is characterized by active uptake into cancer cells and macrophages where it is localized in the lysosomes and macrophagosomes. After completing its function, the polymer depot is gradually degraded and the debris is excluded from the body.
Collaboration
First Medical Faculty, Charles University, Czech Republic, Prague (Dr. Luděk Šefc group, number of joint projects).
Institute of Molecular and Translational Medicine, Olomouc, Czech Republic (Dr. Marian Hajduch group, e.g., the international infrastructure EATRIS, MEYS LM2015064).
Faculty of Medical Sciences, Radboud University, Nijmegen, Netherlands (Prof Carl G. Figdor group, e.g., the H2020 joint project PRECIOUS EU.2.1.2. 686089).
University of Minnesota, Minneapolis, U.S.A. (Prof. Timothy P. Lodge group, e.g., the MEYS LH14079 joint project).
Oslo University and Oslo Radium Hospital, Oslo, Norway (Prof. Bo Nystrom group, e.g., the EEA Norwegian Fund joint project MTBA 7F14009 project).
University of Hefei, Hefei, China (Prof. Chi Wu group, e.g., the MEYS LH14292 joint project).
Universidade do ABC, Sao Paolo, Brazil (Prof. Fernando Giacomelli group, e.g., the CSF – FAPESP 20-15479J joint project).
Polymer Institute of the Slovak Academy of Sciences (M. Hrubý – member of the scientific council, collaboration with J. Kronek group).
Select publications
Self-assembled thermoresponsive polymeric nanogels for 19F MR imaging.
Biopolymer strategy for the treatment of Wilson´s disease.
Patents
Hrubý, I. Brezaniová, V. Král: Photoactivable nanoparticles for photodynamic applications, method of their preparation, pharmaceutical composition containing these particles and their use. CZ Patent 307681 (Date of filing January 3, 2019).