A new call for the UNESCO/IUPAC Course 2021/2022.
You can send your applications till February 21, 2021.
Research projects for UNESCO/IUPAC Course 2021-2022
|Hynek Beneš 1||
Ionic liquids immobilized on 2D nanoparticles and their use for ring-opening polymerization of cyclic monomers
The ring opening polymerization (ROP) of cyclic monomers is by far the preferred synthesis of linear aliphatic polyesters, polyamides, polycarbonates, etc. due to its versatility, mild reaction conditions, solvent-free (bulk) conditions and no volatile by-product formation. Recently, ionic liquids (IL)s have been investigated by our groups and other research teams as ROP catalysts / initiators of lactones, lactide, lactam, epoxides, etc. IL-based catalysts are often highly viscous compounds with limited mass transfer throughout the reaction mixture. Moreover, a large amount (more than 10 wt.%) of ILs is often necessary, which is environmentally as well as economically unfavourable. All these issues might be overcome by (nano)confinement of ILs onto solid (nano)support. In this project, novel water-free 2D nanoparticles, called layered double alkoxides (LDA) will be first synthesized in analogical way to LDH using metal (Ca, Mg) alkoxides (methoxides, ethoxides) instead of metal hydrates. Then, the synthesized LDA will be modified by selected ILs in order to obtaine 2D nanoparticles with the immobilized IL. Finally, these nanoparticles will be tested as catalysts / initiators for ROP of cyclic monomers (preferentially bio-based) as well as nanofillers for in-situ preparation of bio-based nanocomposites with potential application in active packaging.
|Hynek Beneš 2||
Bio-based epoxy resins derived from divanillin
The worldwide environmental concerns have recently led to development of novel polymers based on renewable (bio-) resources. In this project, bio-based epoxy resins derived from divanillin precursors will be explored as eco-friendly substitutes of traditional petrochemical DGEBA-based epoxides. Epoxidized divanillin-based precursors will be first synthesized and structurally characterized. Subsequently, the synthesized precursors will be crosslinked with commercially available bio-based amine hardeners to receive divanillin-based epoxy thermosets. The progress and kinetics of epoxy crosslinking reaction will be studied and structure-related properties of the final epoxy networks will be explored.
|Hynek Beneš 3||
Nanocomposite hydrogels based on renewable itaconic acid
This recent sustainable chemistry concept has promoted investigations using various renewable (bio-) resources (for synthesis of novel polymeric materials). Itaconic acid has been recognized as one of the most promising bio-based building blocks in modern chemical industry. In this project, nanocomposite hydrogels based on itaconic acid will be explored. Natural and synthetic phyllosilicate cationic nanoparticles (hectorite - Laponite XLG, sodium montmorillonite, calcium bentonite, mica, kaolinite) differing in chemical structure and cation exchange capacity will be tested as suitable nanofillers for itaconic-based hydrogels. Selection of effective exfoliating/dispersing agents, which will ensure nanoparticle delamination and dispersion stability, will be another key factor. In this step, mainly phosphates with different overall anion charges will be used with the aim to find optimal nanoparticle/dispersing agent composition and conditions for nanoparticle exfoliation.
|Jiri Brus 1||
MOF and COF materials for Li-ion batteries: synthesis, structure and ionic dynamics
The development of hybrid and full electric vehicles raises the demand for electrical energy generation and storage devices. Well-defined porous architecture that allow Li-ions to be stored and reversibly inserted/extracted, predetermines MOF and COF materials to be explored as electrode as well as electrolyte materials for Li-batteries (LiBs). The aim of this UNESCO project is to develop a novel class of these framework materials modified by metallacarborane compounds and find a suitable polymer matrix allowing to reach optimal flexibility and ionic conductivity in the absence of solvent molecules. The project work includes preparation of the composite materials and their detailed physicochemical and structural characterization.
|Jiri Brus 2||
NMR crystallography of active pharmaceutical ingredients
Lowering the computational cost and at the same time increasing the robustness of the crystal structure prediction-based NMR crystallography approach is currently a key step for successful structure determination of powdered organic solids. This UNESCO project thus aims at analyses of the crystal-symmetry elements together with other geometry parameters in order to find and implement structural constraints and/or restraints into the NMR crystallography protocol. In addition, extensive database searches of the investigated structural motifs will be used.
Study of polymeric and hybrid materials for photonics
The research work in the frame of UNESCO course will be focused on investigations of hybrid materials based on perovskites and conjugated polymers for potential photonic applications (such as photovoltaic devices, photodetectors, solar cells, light-emitting devices, memories, sensors and etc.). It includes preparation of thin films of selected polymeric and perovskite materials and their hybrid layers, study of their properties (absorption, photoluminescence, photoconductivity, etc.), and further also preparation and characterization of appropriate photonic devices. The work will be mainly experimental. The laboratory equipment enables preparation of thin films and study of their properties, and also preparation and characterization of photonic devices in an inert atmosphere. A theoretical knowledge of the applicant can be also utilized, in particular for the interpretation and modelling of experimental data.
|Miroslava Dušková Smrčková||
Resins for 3D-printing of hydrogels for mechanobiological studies
At present, tremendous development of additive manufacturing methods opens new possibilities to create relatively easily structurally complex 3D objects on small size scale. In tissue engineering, the synthetic biocompatible hydrogels provide excellent milieu for cell culture or serve as implant materials while in both applications, the gels must be precisely built in 3D space and contain connected channels (open pores). By utilization of 3D printing methods, specifically 3D droplet deposition and 3D micro extrusion combined with application of newly synthetized printing resins obtained by advanced synthetic methods, one should be able to create demanded hydrogel objects with high spatial precision. We are seeking enthusiasts to develop CAD models of 3D functional hydrogels of complex morphology and transfer these models to printable format and to investigate the printing process with the original printing set-up using in-house designed printing resins. The project is also open to dedicated synthetic chemist who will be responsible for resin design and synthesis. The candidate should be acquainted with the 3D printing processes, CAD and STL formats and/or with chemistry and physics of polymers, and methods of controlled radical polymerization. The work may include chemical synthesis or 3D printing engineering depending on the candidate skills and preference. The candidate should be acquainted with chemistry, physical chemistry and physics of polymers and should have a sufficient knowledge of the physical methods mentioned above.
Miroslava Dušková Smrčková
Bio-based functional precursors for antibacterial and antiviral coatings: design and characterization
High performance coatings based on polymer networks are indispensable for the protection of many interior and exterior objects. Recently, the ability of surface coating to deactivate bacteria and viruses became one of the most demanding function of coatings for public as well as home interiors and equipment. In our laboratory, we developed a novel versatile high-performance and high-strength system for polymeric coatings and as a binder for antiviral and antibacterial additives.
Xeno-free enzymatically degradable polymer materials for 4D bioprinting
Current biology has opened new avenues in biotechnological R&D aimed at ex vivo building 3D structures that closely resemble tissues/organs of living organisms. Despite the self-organizing capacity of cells, extracellular 3D support is still envisioned to promote the establishment of proper tissue morphologies. 3D bioprinting is an attractive option of how cells can be positioned into the right locations and supported in their development. The advanced concept is so-called 4D bioprinting, defined by materials capable of post-printing responsiveness to stimuli. The key limitation of this approach lays in the suboptimal chemistry of biomaterials.
Biodegradable in-situ composites with dual micro-nano-sized reinforcement
Performance of eco-composites is limited especially by parameters of organic nano- and microsized reinforcement. The proposed research deals with upgrading of structures formed in-situ by hot or cold drawing of blends of biodegradable polymers by complex effect of organic nanocrystals (ON) with targeted modification. This consists in reinforcement, support or even enabling of drawing, increasing of dimensional stability of fibers by oriented crystals formation that affects the structure and parameters of interface based on localization and arrangement of ON including formation of novel hierarchical structures. The goal is to get a base for development of high-performance eco-composites capable of thermoplastic processing and additive manufacturing.
|Dana Kubies 1||
Self-assembled multilayer systems based on naturally-derived materials for tunable protein release
The layer-by-layer (LbL) deposition method is a powerful technique for fabrication of multilayer polyelectrolyte nanofilms by complementary interactions between subsequently deposited layers of positively and negatively charged polymers or materials. The LbL deposition has been widely used to produce biocompatible self-assembled coatings as reservoirs of fragile biomacromolecules (e.g., growth factors). The project aims to obtain degradable multilayer LbL coatings for sequential protein release, which are based on cationically modified chitosan or dextran or synthetic dimethylaminoethyl methacrylate-based copolymers a polycation and heparin as a polyanion. Growth factors, such as VEGF, FGF-2 and others, will be incorporated within the LbL film in form of complexes with heparin. LbL films will be studied in terms of assembly/disassembly dynamics, physicochemical properties by advanced instrumental techniques, such as SPR, QCM-D, AFM or CLSM, as well as in vitro biological activities. The bioactivity of loaded growth factors will be assessed by measuring their ability to stimulate proliferation and differentiation of endothelial cells.
|Dana Kubies 2||
Systems for delivery of pro-angiogenic growth factors to support vascularization of polymer scaffolds
In tissue engineering applications, angiogenesis is considered as a crucial step of the tissue-engineered graft or scaffold integration with the host body. Approaches based on freely administrated growth factors (GF) supporting vascularization (such as VEGF or FGF-2), however, have not led to positive results until now. Therefore methods for introduction of pro-angiogenic factors in a control manner using scaffold-based delivery are intensively investigated. One of the strategies consists in incorporation of GFs into microparticles. The project aims to prepare stabile polyelectrolyte microparticles loaded with GFs, to study their physico-chemical properties (e.g., size, zeta potential), loading efficiency and in vitro release of growth factors. The bioactivity of loaded growth factors will be assessed by measuring their ability to stimulate proliferation and differentiation of endothelial cells. Further, the topic is also focused on development of methods for introduction of GF-loaded microparticles into 3D macroporous polymer scaffolds.
Polythiophene derived water-soluble polyelectrolytes for electron transport layers
For photovoltaic applications, water-soluble polyelectrolytes with Red/Ox characteristics will be prepared and analysed morphologically and electrochemically. In the chemistry laboratory, the student will learn how to obtain a polymer by introduction of sidechains to a backbone, and how to synthesize and polymerize a monomer. To verify the synthesis, chemical analyses like GPC, NMR, IR, and elemental analysis will be performed, and the participant will be taught how to plan them and interpret the results. Further analyses will be conducted to determine the physical properties requested from photovoltaic devices, above all, Red/Ox voltages and HOMO and LUMO levels measured in electrochemical cell, ellipsometry, and impedance spectroscopy. Besides the technical skills, the participant will be introduced to samples and laboratory management, scientific method, and scientific literature consultation and production.
Polymer gas separation membranes and membrane contactors
New polymeric and composite materials, based on special polymers (polyimides, polypyrrole, polyaniline, polyvinylidenefluoride) will be synthesized and utilized for preparation of membranes. Physico-chemical properties of the prepared materials will be characterized. Gas transport properties (permeabilities and sorptions) of membranes will be measured and related to their morphology observed by SEM or AFM. The aim is optimizing membrane performance for hydrogen technology and membrane contactors.
Temperature responsive grafted polymer brushes with glass-rubber transitions at physiological temperatures as coatings for protein adsorption and cell cultivation
Growing attention is paid on the creation of ‘smart’ artificial materials with switchable properties, which not only exhibit protein adsorption triggered by external factors, but also actively promote desired cell responses in a controllable manner. However, direct biomedical investigations of the thermo-responsive grafted polymer brushes with other mechanism of the temperature response than lower critical solution temperature has not been reported due to the fact that temperature transitions predominately occur well beyond the range of physiological conditions.
Peptide nucleic acids/polymer brush based biosensing platforms for the label-free detection of blood circulating cell-free nucleic acid fragments
Functional and conformationally restricted DNA analogs, such as peptide nucleic acids (PNAs) can possibly enhance biosensor sensitivity and selectivity when used as biorecognition elements of surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) biosensors. The versatility of PNAs can be even increased if they are bound to a passive background of polymer brushes that cancel out the non-specific protein adsorption from blood plasma or serum. Such PNA/polymer brush-based biosensors can be used to target blood circulating cell-free DNA (cfDNA) fragments stemming from cancerous cells and tumors, and thus help the early cancer diagnosis.
Surface modification of PDMS-based microfluidic devices towards biomedical applications
PDMS-based microfluidic devices have become important tools in the biomedical field providing a number of advantageous features for microscale biochemical synthesis and characterization. The popularity of these devices is mainly the result of their relatively simple fabrication, enhanced performance, and reduced sample consumption and analysis time in comparison with other methods. However, a major drawback is PDMS hydrophobicity leading to significant nonspecific biomolecular adsorption limiting bio-applications of such devices. Hence, this project focuses on surface modification methods to prevent biofouling of PDMS surfaces towards increasing their hydrophilicity and expanding their usage. Accordingly, polymer brushes derived from different hydrophilic monomers are intended to be polymerized by living controlled radical polymerization techniques (such as ATRP or RAFT) on the surface of PDMS microfluidic chips. The resulting surface properties will be characterized using contact angle measurements, ellipsometry, XPS, AFM and fluorescence microscopy. Furthermore, anti-fouling properties will be evaluated using model proteins and blood plasma. Modified chips will be produces and new non-fouling microfluidic devices based on these chips will be further exploited in affinity separation assays.
New polymers for cell encapsulation
A next-generation cure for diseases such as type 1 diabetes relies on the transplantation of cells immunoprotected by semipermeable membranes made of non-covalently crosslinked hydrogels. In most cases, these membranes have the form of ionotropically crosslinked alginate-derived microspheres. However, these simple designs usually do not allow for the fine-tuning of membrane properties (such as the molecular weight cut-off) and can also suffer from long-term structural instability. This problem may be solved by introducing additional polymeric components that form a secondary non-covalent network based on polyelectrolyte complexation. The so-called PMCG microcapsule, composed of sodium alginate, sodium sulfate, and polymethylene-co-cyanoguanidine, is a good example of such an approach. Nevertheless, the PMCG microcapsule still suffers from certain drawbacks pertaining to its poorly defined starting materials and structural changes in vivo.
Carboxybetaine derived polymer brushes for non-fouling surface coatings
Carboxybetaine acryl- and methacrylamides and related zwitterionic polymers have been widely and comprehensively studied because of their unique properties. However, the complex nature of the carboxybetaine-derived polymer brushes and the connection between the polymer structure and performance are still not fully unveiled and their study is of great scientific interest.
|Zdeněk Starý 1||
Rheology of particle filled polymer melts
The project concerns rheological properties of particle-filled polymers with a special attention to their elasticity in the molten state. Although the effects induced by the presence of filler particles on melt elasticity are reported in literature, understanding their origins and mechanisms is still lacking. Systematic study of the influence of particle size, concentration and surface modification on melts elasticity in linear and non-linear viscoelastic range will be performed. The filled systems will be studied experimentally by different rheological techniques (oscillatory shear, capillary rheometry). Structure of the composites will be visualized by electron microscopy. The applicant should have a basic background in polymer physics and polymer processing. Experience with rheological characterization of polymeric materials is an advantage.
|Zdeněk Starý 2||
Polymeric materials for advanced applications: structure, properties and processing
Nowadays new applications and processing technologies place new and bigger demands on polymeric materials. Materials for 3D printing or electrically conductive polymer composites can serve as typical examples. In most cases these systems have a heterogeneous phase structure, which influences the end-use properties of the final material to a large extent. The aim of the work is a description of relationships between structure and properties of materials relevant for practical applications. Work activities include a preparation of polymeric materials and structural investigations by means of electron microscopy. Furthermore, mechanical and flow behaviour of prepared materials will be studied in detail.
Self-assembling LC-tethered copolymers as starting materials for smart elastomers and liquids
Novel smart elastomeric polymers will be synthesized, their material properties will be explored and fine-tuned. The polymers will be mainly based on polydimethylsiloxane (PDMS) non-covalently crosslinked by liquid-crystalline (LC) units attached to the PDMS macromolecules. The smart properties should include temperature-induced switching between several states like stiff elastomer, plastic elastomer, viscoelastic melt and thin melt. Additional smart functions should include self-healing, shape memory (in more complex derivatives), and a potential for developing light-responsiveness. The elastomers also should be fusible and hence reprocessible (recyclable).
Synthesis and study of advanced nanocomposites and hydrogels
This project involves synthesis and characterisation of nanocomposites and hydrogels, with enhanced mechanical properties like high elastic extensibility, high elastic moduli. The materials will be based on acrylamides and acrylates and will be reinforced by inorganic fillers. As fillers we will use different kinds of inorganic particles (silica, titania), nano-plates (clay) or aluminium phosphate nanorods. The latter will be synthesized and modified. In addition to the synthesis, the rheological properties during the formation of nanocomposites (gelation) and the thermomechanical properties of the final products (DMTA) will be characterized. Further characterization of products will be performed in cooperation with departments of our institute: especially morphology (SEM, TEM, WAXS, SAXS), chemical microstructure (NMR).
Magnetic polymer composites as multifunctional tools for regenerative medicine
The variety of polymers and their relatively easy processing make them ideal for designing scaffolds intended for tissue engineering and regenerative medicine. Their multifunctionality can be achieved by conjugation with biologically active molecules or modification with inorganic nanoparticles. In this project, both pathways will be implemented to design and fabricate scaffolds with antibacterial, antioxidant and magnetic properties. The antibacterial and antioxidant activity will be achieved by the use of poly(ε-caprolactone)-chitosan blends, in which chitosan will be conjugated or crosslinked with phenolic compounds, such as gallic or tannic acid. The magnetic properties will be attained by introduction of magnetic nanoparticles into polymer matrix. The 3D architecture of the scaffolds will depend on the fabrication method – fibrous materials will be prepared via electrospinning, while highly porous materials will be prepared by solvent casting/polymer leaching method. The scaffolds will be characterized in terms of parameters essential for biological response, i.e., mechanical, surface (roughness, wettability, surface energy) and antioxidant properties, as well as microbiological and in vitro characteristics.
Polysaccharide microgels for tissue engineering
Microgels represent crosslinked soft hydrophilic hydrogel microparticles which can be fabricated from a wide range of natural or synthetic polymers. Due to their unique properties, microgels are recently very attractive for tissue engineering because they can be implemented into polymer scaffolds where they serve as a supportive depot of various proteins or growth factors. Within this project, microgels will be prepared by horseradish peroxidase/H2O2-mediated crosslinking in inverse suspension from polysaccharide precursors with the aim to regulate size and size distribution of final microgels. Various microgelation conditions including the type and concentration of surfactant and the manner of homogenization will be tuned to obtain polysaccharide microgels with the size in a range of tens of micrometers. Finally, the developed microgels will be loaded with growth factor and the microgel loading capacity will be studied and optimized.
Biodegradable polymer systems for medical applications
Biodegradable and biocompatible polymer systems show numerous applications in both human and veterinary medicine. We have recently developed and patented multiphase polymer systems based on thermoplasticized starch (TPS), polycaprolactone (PCL), and antibiotics (ATB). Morphology and properties of these systems can be adjusted by their composition and targeted phase structure modification during the processing. TPS/PCL/ATB systems can be employed in treatment of strong local infections such as osteomyelitis. The project comprises preparation of the systems (by combination of starch plasticization, solution casting and melt mixing), optimization of their phase structure (targeted modification of processing conditions), characterization of their morphology (electron microscopy), properties (rheology, microindentation etc.), and participation in medical tests in collaboration with a local hospital (FN Motol; treatment of local infects, biodegradability).
Modeling of the charge carrier transport in linear polymer materials
Organic electronic devices possess many advantages over their classical counterparts, like relatively low price and easy solution processability, good mechanical properties (flexibility, low weight) and possibility of tuning performance parameters by modification of the molecular structure of the materials. Recently, an increasing attention has been paid to the organic field-effect transistors (OFETs), which are used as building blocks of simple logic units and volatile memories, in different kinds of sensors, or for switching of particular pixels in the active matrix organic light emitting diode (AMOLED) displays. However, despite many successes, the charge carrier mobility of OFETs and stability of their transport characteristics is still considerably worse than that of inorganic transistors. Thus, proper understanding of the charge transport mechanism in the OFETs is very important.
Different electrochemical methods of deposition of thin polymer film for bio-sensor applications
Selective detection of various biologically important ions or molecules, bacteria, etc., is performed by bio-sensors. Semiconducting polymers are the class of organic material that could explicitly interact with the medium and change their electrical and/or redox properties. The synthesis of durable, reproducible and sensitive semiconducting film is still a challenge. In the current project the different electrochemical methods (such as cyclic voltammetry, chronopotentiometry, and chronoamperometry) will be used in order to obtain such films from monomer 3,4-ethylenedioxythiophene and its derivatives. Furthermore, various electrochemical techniques (such as galvanostatic charge – discharge, electrochemical impedance spectroscopy, etc.) will be applied to characterize deposited film for bio-sensor applications.