Full name of the USI:
Complex of equipment for spectral measurements of supercritical fluids
Abbreviated name: USI:
Fluid-Spectrum
Organization:
G.A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences
Head:
Khodov Ilya Anatolyevich, Director of the complex of equipment for spectral measurements of supercritical fluids, Candidate of Physical and Mathematical Sciences
Contacts:
Tel. +7 (4932) 351869, e-mail: fluid-spektr@isc-ras.ru
The USI Fluid-Spectrum was established in 2018 and reorganized in 2019.
Address:
• Federal district: Central
• Region: Ivanovo oblast
• 1 Akademicheskaya Street, Ivanovo, 153045, Russia
Submit an application
Official documents:
• Standard works and services
• Program of USI medium term development (5 years)
• USI workplan
• Equipment and methods
• Rules of competitive selection of applications from third parties
• USI regulations
• Provision of access to USI
• Application form
• Draft contract
Main research directions of the USI:
• Solution chemistry, theory of chemical engineering processes in liquid media;
• Chemistry and technology of obtaining and modifying oxide, polymer, and hybrid nanomaterials in solutions;
• Design of novel drug forms and biomedical materials.
Description and main advantages of the USI:
The ISC RAS complex of molecular fluid spectroscopy apparatuses is the world's only facility equipped with special cells for obtaining infrared (IR) vibrational spectra and nuclear magnetic resonance (NMR) spectra at supercritical parameters of state. A unique optical high-temperature high-pressure cell has been designed and constructed at the Institute to achieve its research goals. The cell is made of special steel, which makes it suitable for the use at a broad range of temperature and pressure values up to 1000 bar and ~300°C. The cutting-edge optical window sealing system made from Graphlex, a carbonaceous material, allows scientists to make long-time experiments at high pressures and temperatures, eliminating any pressure loss in the cell. One of the most important features of the cell is that it is possible to quickly change its inner geometry, in particular the optical length of the sample, depending on the requirements of the study being conducted. The cell structure is suitable for studying both single-component (liquid, gas, supercritical fluid) and multi-component and multi-phase (liquid-gas, liquid-supercritical fluid, liquid-solid, supercritical fluid-solid, etc.) systems.
In addition to the fluid IR spectroscopy unit, Fluid-Spectrum is equipped with a fluid NMR spectroscopy instrument, in which pressure is produced inside a special resistive cell. Such cells are made of various materials (plastic, glass, quartz, sapphire and zirconium dioxide). Their foreign analogues are produced from zirconium dioxide but it is unsuitable for studying aggressive media (hydrofluoric and concentrated sulfuric acids). That is why the NMR cell used at the USI, as well as the one for IR studies, is made from sapphire that is more resistant to aggressive media and its expansion coefficient is relatively independent of temperature, which prevents temperature gradient effects on spectral measurements. The cell is equipped with a special valve made from a nonmagnetic material for gas supply pressure regulation. The functionality of the molecular fluid spectroscopy complex will be considerably extended by modernizing the cell for NMR studies. The main goal of the modernization is to increase the main technical characteristics, namely pressure stability in the NMR cell.
The most significant research results (a short description):
In the last few years, the molecular fluid spectroscopy instrument has been employed in multi-disciplinary studies of biologically active substances in a fluid solution. One of the projects was a comprehensive study of paracetamol solubility in supercritical carbon dioxide and dissolution kinetics within a wide range of temperature and pressure values [European Journal of Pharmaceutical Sciences].
Another study concerned the correlation between the conformational state of molecules of biologically active substances (paracetamol and ibuprofen) in the supercritical carbon dioxide phase being in equilibrium with the crystal form of the compound under study [Journal of Molecular Liquids].
The investigation of the methanol-scCO2 binary solvent revealed that the initial components of the mixture could interact with each other yielding dimethyl-carbonate and allowed the reaction kinetic parameters to be determined within a wide temperature range [Journal of Molecular Liquids].
A group of scientists from the Institute have for the first time made a comprehensive study of molecular conformations of mefenamic acid in its saturated solution in supercritical carbon dioxide being in contact with the bottom phase containing various polymorphs of mefenamic acid under isochoric heating within the temperature range of 80–220°C. [The Journal of Supercritical Fluids]
A unique self-consistent approach has been proposed for controlling polymorphic transformations of drug compounds through screening conformational diversity of their molecules in the supercritical fluid state being in equilibrium with their solid phase. It was established that heating leads to the appearance of a conformational crossover of carbamazepine molecules in the fluid phase, which suggests that there is a polymorphic transformation in the carbamazepine solid phase being in equilibrium with the liquid solution phase [Spectrochimical Acta Part A: Molecular and Biomolecular Spectroscopy].
USI Board of Experts:
Chairperson Doctor of Chemical Sciences Mamardashvili Nugzar Zhorayevich
Vice-Chairperson Candidate of Physical and Mathematical Sciences Khodov Ilya Anatolievich
Secretary of the Board of Experts Sobornova Valentina Vladislavovna
Doctor of Chemical Sciences Syrbu Sergei Aleksandrovich
Candidate of Chemical Sciences Oparin Roman Dmitrievich
Candidate of Chemical Sciences Dyshin Aleksei Aleksandrovich
Technical characteristics:
The molecular fluid spectroscopy complex is equipped with a special cell for measuring vibrational infra-red (IR) spectra as well as nuclear molecular resonance (NMR) spectra within a wide range of parameters of state, including supercritical conditions. The unique system of pressure and temperature control developed for the IR spectroscopy complex allows making measurements in the range of P= 1 bar - 1000 bar and maintaining pressure with an accuracy of 0.1 bar and in the range from room temperature to T~400°C with an accuracy of 1°С. The universal character of the system allows it to be used with various types of experimental cells (for IR and NMR spectroscopy), reactors for various processes based on supercritical fluid technologies, namely, rapid expansion of supercritical solutions (RESS).
The molecular fluid spectroscopy complex is equipped with a special cell for measuring vibrational infra-red (IR) spectra as well as nuclear molecular resonance (NMR) spectra within a wide range of parameters of state, including supercritical conditions. The unique system of pressure and temperature control developed for the IR spectroscopy complex allows making measurements in the range of P= 1 bar - 1000 bar and maintaining pressure with an accuracy of 0.1 bar and in the range from room temperature to T~400°C with an accuracy of 1°С. The universal character of the system allows it to be used with various types of experimental cells (for IR and NMR spectroscopy), reactors for various processes based on supercritical fluid technologies, namely, rapid expansion of supercritical solutions (RESS).
