Topic title |
Possible scientific supervisors |
Source of funding |
Synthesis and characterization of new structure low-molar-mass organic semiconductors for OLEDs
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prof. dr. Saulius GRIGALEVIČIUS |
state-funded |
Research Topic Summary.
Recent advances in organic optoelectronics, particularly in efficient organic light-emitting devices (OLEDs), have called for new electro-active organic materials as well as for new device technologies. Small OLED-based displays already generate hundreds of millions of dollars. Larger OLED displays will penetrate the television market in the not-too-distant future. Nowadays white displays play important role in lightening. Further advances of these devices substantially rely on development and studying of high-performance organic charge-transport and emitting materials, theoretical understanding of charge and energy transport in the organic systems and their well-balanced application in OLED devices.
Despite their recent progress, OLEDs are still dealing with the issues of efficient and balanced carrier injection and transportation because of large difference of barrier heights and low carrier mobility. Unbalanced hole and electron current in OLEDs makes the recombination zone narrower, thereby leading to less efficiency with high roll-off and shorter lifetime. Various approaches for efficient hole injection have been also adopted in the past, however, hole transport phenomena is still dealing with the critical issues like low hole mobility, high injection barrier between two highest occupied molecular orbital levels, and morphological and thermal instability caused by Joule heating. Hence, hole-transporting materials possessing low ionization potential for efficient hole injection, high hole mobility, thermal durability and morphological stability with high glass transition temperature are still demanding. Efficiency of OLED devices would be increased several times by using the materials in multilayer structures.
Objective of the project- synthesis, characterization and application in OLED devices of new structure electroactive materials having efficient charge transporting properties in order to develop devices having higher efficiencies than those of OLEDs using commercially available charge transporting derivatives.
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Synthesis of biologically active heterocyclic derivatives of N-substituted amino acids
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m.d. dr. Ingrida TUMOSIENĖ |
state-funded |
Research Topic Summary.
Heterocyclic compounds are important biologically active substances. Modern medicine uses natural, modified natural or synthetic compounds containing various heterocyclic moieties possessing various pharmacological activities - antibiotics, antifungals, analgesics, anticancer, anti-inflammatory agents, etc. One of the challenges of modern medicine is the growing resistance of pathogens to existing widely used drugs. The search for new functional materials involves both the modification of the structure of known compounds by their functionalization and the development of new original molecules, the study of their structure and properties. Five- and six-membered heterocyclic compounds possess antibacterial, fungicidal, anticancer, antiviral, anti-inflammatory, analgesic, etc. properties. A widely used method for the preparation of heterocyclic compounds is the cyclization reactions of N-substituted amino acids and their derivatives, in which another moiety tuning biological activity is introduced into the structure of the target molecule.
The planned research work would involve synthesis of potentially biologically active compounds bearing variously modified five- and six-membered heterocycles via condensation reactions of carboxylic acids and their derivatives and investigation of their chemical and biological properties.
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Synthesis and investigation of N-aryl substituted amino acids and their derivatives with azole and azine moiety
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prof. habil. dr. Vytautas MICKEVIČIUS |
state-funded |
Research Topic Summary.
As the global ecological situation deteriorates, human immunity weakens, new diseases spread, new bacterial strains emerge, viruses mutate, the activity of the medicines produced decreases or they become completely inactive. Therefore, the search for new biologically active substances and the development of medicines is an important ongoing process that enables vital systems to function normally. Heterocyclic compounds account for more than half of all known organic compounds. Many biologically active compounds with a amino acids moiety are known to be used in the development of pharmaceutically important preparations. The synthesis of nitrogen-containing heterocyclic systems has been extremely popular in pharmaceutical and agrochemical industries. The nitrogen-containing heterocycles are found in abundance in most of medicinal compounds. Azoles and azines are five- and six-membered heterocyclic compounds with one or several heteroatoms in the ring. The nitrogen, oxygen, and sulphur heterocycles are an attractive source of compounds for the identification of new biological probes. Azoles and azines are found to be associated with various biological activities such as antiviral, antimicrobial, antifungal, anticancer, anti-inflammatory, antihypertensive, anti-HIV, anticoagulant, antiarrhythmic, antidepressant, antidiabetic, etc. N-Substituted amino acids, hydrazides and hydrazones of carboxylic acids are used in the synthesis of five- and six-membered heterocyclic compounds containing one, two or three nitrogen atoms in a heterocycle. Pyrroles are important synthons in the synthesis of natural products. The pyrazole, thiazole scaffolds represents a common motif in many pharmaceutical active and remarkable compounds demonstrating a wide range of pharmacological, antiproliferative, crop protection activities. The triazole nucleus is one of the most important heterocycles; it is a feature of natural products and predominates among the medicinal agents. The widespread use of 1,3,4-oxadiazoles as a scaffold in medicinal chemistry establishes this moiety as an important bioactive class of heterocycles. The task of this research is development of the synthesis methods for new functionalized azoles and azines, containing amino acids and their derivatives, aliphatic, aromatic, heterocyclic, carbonylic, quinone fragments, investigation of chemical and biological properties and reactivity of these compounds under different conditions. The practical significance of the work will be described by the investigation of the antibacterial properties of some of the synthesized compounds and the evaluation of the dependence of their activity on the chemical structure. Based on the obtained data, it will be possible to develop a methodology for targeted synthesis of antimicrobial agents, intermediates for organic synthesis.
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Synthesis, structure and properties of new aza-heterocyclic compounds |
prof. habil. dr. Algirdas ŠAČKUS |
state-funded |
Valorisation of poorly studied plant species by evaluating their phytochemical composition and functional properties
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prof. dr. Petras Rimantas VENSKUTONIS |
state-funded |
Research Topic Summary.
The plants biosynthesize various secondary metabolism products, including bioactive compounds (e.g. antioxidants, antimicrobials, anticancerogenic molecules), which may find applications in food additives, functional ingredients for nutraceuticals, cosmetics, pharmaceuticals and other purposes. Considering that there are thousands of species in the Plant Kingdom and many of them are very poorly studies, it may be expected to discover (identify) new structures possessing beneficial properties, e.g. antioxidant capacity, antimicrobial and enzyme inhibitory activity, etc. The candidate species may be selected from the plants growing in Lithuania and other regions; e.g. until now performed preliminary studies have shown that the extracts from such plants possess strong radical scavenging capacity.
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Studies of self-assembling biopolymeric amphiphiles and their properties
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prof. dr. Ramunė RUTKAITĖ |
state-funded |
Research Topic Summary.
Numerous approaches have been developed for the self-assembly of natural or synthetic amphiphiles into soft core-shell nano- or microobjects which are of great interest in various fields. Among these amphiphilic molecules, amphiphiles containing natural blocks, such as polysaccharides, have attracted the most attention because they are non-toxic, non-immunogenic, biocompatible, biodegradable, and renewable. Polysaccharide based amphiphilic copolymers might represent a new class of biopolymeric materials with potential applications in different fields such as plastic industry, detergency, and also as the pharmaceutics where the design of nano or microdevices carrying a polysaccharide chains can be also of interest for therapy, vaccination and diagnostic purposes.
The aim of this research work – to obtain various modified polysaccharide structures having both hydrophilic and lipophilic groups and to explore their properties in the light of different potential applications.
During the course of the project chemical and physical modification of natural polysaccharides will be performed to obtain the derivatives of different structure, amphiphilicity, charge density (either neutral or charged), molecular weight etc. The self-aggregation behavior of obtained amphiphilic polysaccharides in water via formation of various structures e.g. hydrogel nanoparticles, micelles, polymersomes, oil in water emulsions etc. as well as their properties will be also assessed. The developed materials will be also tested in some applications such as controlled delivery of target compounds via stimuli responses e.g. pH, temperature, enzyme-degradation etc.
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Design, synthesis and investigation of novel heterocyclic compounds |
doc. dr. Eglė ARBAČIAUSKIENĖ |
state-funded |
Fibrous pharmaceutical delivery systems
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vyr.m.d. dr. Edvinas KRUGLY |
state-funded |
Research Topic Summary.
During doctoral studies research will be carried out in order to develop a functional fibrous drug delivery system with controlled drug release for the treatment of cancer metastases.
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Synthesis, investigation and application of new organic hole transporting materials
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v.m.d. dr. Jūratė SIMOKAITIENĖ |
state-funded |
Research Topic Summary.
During last few years, scientific interest in organic and hybrid solar cells significantly increased. The most interesting and promising photovoltaic devices in which organic semiconductors are used are perovskite solar-cells which demonstrate outstanding progress. However, this promising technology still has some drawbacks which can be avoided by careful research. Usage of this hole-transporting material allows to obtain efficient perovskite solar cells (PSC), however its synthesis is complicated and expensive. Design and synthesis of inexpensive hole-transporting semiconductors can be essential step towards further commercialization of perovskite solar cells. In this work, new, effective and inexpensive organic hole-transporting materials with low ionization potentials will be design, synthesized and characterized.
The main idea of the project is to develop inexpensive, easily obtainable organic hole-transporting materials with low ionization potentials (<5.3 eV), high thermal and photochemical stability, high solubility, high glass transition temperature (>1000C), high hole mobility (>10-4 cm2/V.s) for efficient and stable perovskite solar cells (PVCs).
The objective of the project is design, synthesis and investigation of effective organic hole-transporting material with low ionization potentials and fabrication and characterization PSCs based on the newly synthesized materials.
Tasks which are set to achieve abovementioned idea and objective:
1. Design of the structures of organic compounds using density functional theory (DFT)
2. Synthesis and its optimization for achieving the simplest synthetic pathways, highest yields of the products and the most environmentally friendly reaction conditions
3. Investigation of thermal, electrochemical, photophysical, charge-transporting properties of the synthesized materials for estimation of their applicability in PSCs.
4. Fabrication and characterization of PSCs.
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Synthesis and electrocatalytic activity of nanostructured oxide films for water electrolysis and CO2 reduction
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doc. dr. Agnė ŠULČIŪTĖ |
state-funded |
Research Topic Summary.
Hydrogen has the potential to play a significant role in tacling climate change and solving renewable energy storage problems. Water electrolysis driven by renewable electricity is considered to be the most perspective option for the development of so-called hydrogen-based economy. On the other hand, CO2 electrochemical reduction has emerged as a promising method for the conversion of CO2 and water converted into value-added chemical compounds, such as carbon monoxide, formic acid, ethylene or thanol. However, there is a need for developing better electrodes and new catalysts in order to decrease the cost of green hydrogen production or CO2 conversion into valuable chemicals. The aim of the dissertation is relevant to the development of electrochemical technologies for water electrolysis and CO2 reduction. Particular attention will be paid to the search of efficient and low-cost electrocatalysts based on nanostructured metal oxides suitable for the implementation of these processes. In order to achieve the aim, the following tasks are formulated:
1. To synthesize manostructured mixed oxide films on stainless steel;
2. To evaluate the influence of synthesis conditions on structure, composition and morphology of the prepared films;
3. To study the electrocatalytic activity of the prepared electrodes in water splitting and CO2 electroreduction.
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