Projects / Programmes
January 1, 2004
- December 31, 2008
| Code |
Science |
Field |
Subfield |
| 1.04.00 |
Natural sciences and mathematics |
Chemistry |
|
| Code |
Science |
Field |
| P400 |
Natural sciences and mathematics |
Physical chemistry |
Thermodynamics, calorimetry, spectroscopy, transport properties, electrolyte solutions, polyelectrolytes, polyampholites, surfactants, proteins, nucleic acids, microemulsions, SAXS, water, solvation, hydrophobic interaction, statistical thermodynamics, computer simulations, adsorption, integral equations.
Researchers (29)
Organisations (1)
Abstract
1a) Investigations of aqueous solutions of fullerene based electrolytes are planned (Cerar, Škerjanc). Transport numbers of fullerene-hexamalonate macroion in solutions of different mono- and divalent salts will be measured and, fraction of free ions will be estimated. Experimental results will be compared with the theoretical predictions. SAXS method will be applied to detect eventual presence of aggregates.
b) Temperature and concentration dependence of electric conductivity of multivalent electrolytes in water and mixed solvents will be measured (Bešter-Rogač). The limiting conductivities and association constants in diluted solutions will be obtained and the changes in thermodynamic properties will be determined. The results will be used to analyze the data for more concentrated solutions.
c) Some stereoregular polyelectrolytes will be synthesized (Kogej), and their thermodynamic and transport properties will be studied. Furthermore, we plan to investigate interactions between polyampholytes and surfactants and the influence of surfactant on the complex formation between polyampholytes and biopolymers in aqueous solutions.
d) Osmotic coefficients, enthalpies of dilution, and enthalpies of mixing of ionene solutions with various counterions will be measured at several temperatures (Pohar), and the data will be compared with the theoretical values. The average molecular mass and the radius of gyration will also be determined.
2. We intend to study binding of several antibiotics to DNA using different spectroscopic and calorimetric techniques (Vesnaver, Lah). The results will be compared with the theoretical predictions to learn more about the contributions to the energy and entropy of binding. We wish to investigate how the stability of model G-quadruplexes depends on the DNA sequence and on the nature and concentration of the simple ions present in the solution. We shall proceed with studies of the nature and magnitude of the interactions of substituted amino acids. The energetics of the interactions and stability of the proteins participating in programming the bacteria cell death will be studied.
3. We intend to examine theoretically the binding mechanisms of ligands into the minor groove of DNA, the rules of the molecular recognition of DNA, and to determine thermodynamic binding parameters (Koller, Vesnaver). QM/MM and molecular dynamics methods will be applied. New methods for fast calculation and evaluation of molecular similarity will be considered and applied for potentially pharmacologically interesting structures (Koller, Podlipnik). Structure and reactivity of some polyoxides will be studied.
4. SAXS method will be used to study the structural properties of colloidal dispersions (Jamnik, Bešter-Rogač) and various microemulsions. The systems with interacting scattering structures will be considered theoretically. We also plan the structural investigations of gels.
5. Theoretical study of adsorption in random matrices is planned (Vlachy, Hribar Lee, Urbič). The generalized replica integral equations will be used to study the adsorption for more realistic models of adsorbent. In another project the solvation of chain-like molecules will be investigated using product-reactantant Ornstein-Zernike theory. We will be interested in the properties of confined water (Monte Carlo method, density functional theory). We shall study effects of macroion charge, salt concentration and other parameters on the reaction rate between equally charged species (Vlachy, Reščič). Using the Monte Carlo method we will evaluate the effect of dielectric discontinuity on micellar solution properties. The integral equation theories and Monte Carlo method will be used to study the mixtures of model adhesive liquids (Jamnik).
Significance for science
The studies presented here shall with the help of modern experimental techniques and theoretical methods enrich our basic knowledge in the physical chemistry of solutions and dispersions. Aqueous solutions of electrolytes and (bio)polyelectrolytes play important role in science and technology. Ions, simple and complex, take place in vital processes in our organism. The role of water in these processes, though crucial, is not fully understood yet. There are books written about the 'hydrophobic interaction', but the opinions about its mechanism are not unique. Investigation of protein stability in presence of macromolecules and added salts, studies of ligand binding to DNA, or quantum-chemical similarity studies, are important for pharmaceutical industry and in bioengineering. On the other hand, understanding the properties of polyelectrolytes, surfactants and colloids and their interaction with surfaces is important for ecology and industry. Our experimental studies are closely connected with the theoretical ones: the goal is to understand the properties of matter on a molecular level. Our studies are also important for biomedical sciences; together with a group of Professor K.A. Dill (UC San Francisco) we have been awarded the National Institute of Health USA grant for 8 years altogether. Members of the group are not unknown to their colleagues abroad. Our papers were published in recognized journals as: Proc. Natl. Acad. Sci. US, J. Am. Chem. Soc., Annu. Rev. Phys. Chem., Annu. Rev. Biophys. Biomol. Struct., Trends. Biochem. Sci., J. Phys. Chem. B, J. Chem. Phys., J. Stat. Phys., Langmuir, Biochemistry, Biophys. J., and J. Mol. Biology. In addition we held lectures on international conferences and universities. We have joint papers with researchers from more than ten laboratories in the world. Members of the group serve as reviewers for J. Phys. Chem. B and C, Langmuir, J. Chem. Phys., JACS, PCCP, etc.
Significance for the country
The researchers participating in this project are members of the Physical chemistry Chair at FKKT University of Ljubljana were we serve as educators. We are teaching 30 subjects from physical chemistry and related fields. There are around 1000 students from six different Departments taking these classes. All the classes include laboratory practice after all, Chemistry is an experimental science. Doing research the professors and their coworkers acquire new knowledge and communicate it to students. There is no good school without good teachers; we believe that good teachers can be formed through the process of self–education: the process is called research. We have a long standing collaboration with pharmaceutical and chemical companies Belinka – Perkemija, Lek (Novartis group), Krka d.d, Cinkarna Celje. We have recently signed a long-term contract of collaboration with Krka d.d. Our former PhD student dr. B. Jerman, now employee of Krka d.d., will help in coordinating joint research. In summary, our group is engaged in research in the field of physical chemistry and in transferring this knowledge to students and to industrial practice. We contribute toward strengthening of the national identity and cultural heritage in several other ways. The publications published in distinguished journals and lectures at conferences and Universities abroad contribute toward »putting Slovenia on the map«. In year 2005 our group organized an important IUPAC-sponsored conference on chemistry in solutions (29. ICSC). We hosted around 300 guests (among them Nobel laureate Professor J-M. Lehn); some of them were for the first time in Slovenia. P.I. V. Vlachy is a member of the steering committee for the ICS conferences.
Most important scientific results
Final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Final report,
complete report on dLib.si
