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od 2020-09-20

Dr Kosma Szutkowski  | 1997-10 <> 2017-09

Adiunkt

   WF UAM pokój: 131 / CNBM UAM      +48 61-829-5030       kosma1234(at)hoth.amu.edu.pl
(anti-spam info: the numbers in my email are fake so please remove them all!)

  0000-0002-6091-9049     7801507853     

Zainteresowania naukowe:
Wykorzystanie metod spektroskopii gradientowej MRJ w badaniu zjawisk molekularnej dyfuzji wody w układach liotropowych. Obrazowanie tensora dyfuzji wody w układach anizotropowych.

Procesy wymiany protonowej oraz ich wpływ na zjawiska relaksacji jądrowej w wodzie.

Publikacje           Doktorzy                Seminaria


26.

Szutkowski K., Sikorska E., Bakanovych I., Choudhury A.R., Perdih A., Jurga S., Novic M., Zhukov I.

Structural analysis and dynamic processes of the transmembrane segment inside different micellar environments-implications for the TM4 fragment of the bilitranslocase protein The transmembrane (TM) proteins are gateways for molecular transport across the cell membrane that are often selected as potential targets for drug design. The bilitranslocase (BTL) protein facilitates the uptake of various anions, such as bilirubin, from the blood into the liver cells. As previously established, there are four hydrophobic transmembrane segments (TM1-TM4), which constitute the structure of the transmembrane channel of the BTL protein. In our previous studies, the 3D high-resolution structure of the TM2 and TM3 transmembrane fragments of the BTL in sodium dodecyl sulfate (SDS) micellar media were solved using Nuclear Magnetic Resonance (NMR) spectroscopy and molecular dynamics simulations (MD). The high-resolution 3D structure of the fourth transmembrane region (TM4) of the BTL was evaluated using NMR spectroscopy in two different micellar media, anionic SDS and zwitterionic DPC (dodecylphosphocholine). The presented experimental data revealed the existence of an alpha-helical conformation in the central part of the TM4 in both micellar media. In the case of SDS surfactant, the alpha-helical conformation is observed for the Pro258-Asn269 region. The use of the zwitterionic DPC micelle leads to the formation of an amphipathic alpha-helix, which is characterized by the extension of the central alpha-helix in the TM4 fragment to Phe257-Thr271. The complex character of the dynamic processes in the TM4 peptide within both surfactants was analyzed based on the relaxation data acquired on N-15 and P-31 isotopes. Contrary to previously published and present observations in the SDS micelle, the zwitterionic DPC environment leads to intensive low-frequency molecular dynamic processes in the TM4 fragment.

International Journal of Molecular Sciences, 20(17), 4172 (2019)

DOI: 10.3390/ijms20174172   (Pobrane:  2020-12-30)


25.

Grabowska M., Grześkowiak B.F., Szutkowski K., Wawrzyniak D., Głodowicz P., Barciszewski J., Jurga S., Rolle K., Mrówczyński R.

Nano-mediated delivery of double-stranded RNA for gene therapy of glioblastoma multiforme Glioblastoma multiforme (GBM) is the most common type of malignant gliomas, characterized by genetic instability, intratumoral histopathological variability and unpredictable clinical behavior. Disappointing results in the treatment of gliomas with surgery, radiation and chemotherapy have fueled a search for new therapeutic targets and treatment modalities. Here we report new approach towards RNA interference therapy of glioblastoma multiforme based on the magnetic nanoparticles delivery of the double-stranded RNA (dsRNA) with homological sequences to mRNA of tenascin-C (TN-C), named ATN-RNA. The obtained nanocomposite consisted of polyethyleneimine (PEI) coated magnetic nanoparticles conjugated to the dsRNA show high efficiency in ATN-RNA delivery, resulting not only in significant TN-C expression level suppressesion, but also impairing the tumor cells migration. Moreover, synthesized nanomaterials show high contrast properties in magnetic resonance imaging (MRI) and low cytotoxicity combining with lack of induction of interferon response. We believe that the present work is a successful combination of effective, functional, non-immunostimulatory dsRNA delivery system based on magnetic nanoparticles with high potential for further application in GBM therapy.

PloS ONE, 14(3), e0213852 (2019)

DOI: 10.1371/journal.pone.0213852   (Pobrane:  2020-12-28)


24.

Jędrzak A., Grześkowiak B.F., Coy E., Wojnarowicz J., Szutkowski K., Jurga S., Jesionowski T., Mrówczyński R.

Dendrimer based theranostic nanostructures for combined chemo- and photothermal therapy of liver cancer cells in vitro Here we report the synthesis of multifunctional nanocarriers based on PAMAM dendrimers generation (G) 4.0, 5.0 and 6.0 fixed to polydopamine (PDA) coated magnetite nanoparticles (Fe3O4). Synthesized nanoplatforms were characterized by transmission electron microscopy (TEM), the electrokinetic (zeta) potential, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and magnetic resonance imaging (MRI). Further, we show as a proof of concept that nanocarriers functionalized with G 5.0 could be successfully applied in combined chemo- and photothermal therapy (CT-PTT) of the liver cancer cells. The cooperative effect of the modalities mentioned above led to higher mortality of cancer cells when compared to their individual performance. Moreover, the performed in vitro studies revealed that the application of dual therapy triggered the desired cell death mechanism-apoptosis. Furthermore, performed tests using Magnetic Resonance Imaging (MRI) showed that our materials have competitive contrast properties. Overall, the functionality of dendrimers has been extended by merging them with magnetic nanoparticles resulting in multifunctional hybrid nanostructures that are promising smart drug delivery system for cancer therapy.

Colloids and Surfaces B: Biointerfaces, 173, 698-708 (2019)

DOI: 10.1016/j.colsurfb.2018.10.045   (Pobrane:  2019-03-21)


23.

Szutkowski K., Kołodziejska Ż., Pietralik Z., Zhukov I., Skrzypczak A., Materna K., Kozak M.

Clear distinction between CAC and CMC revealed by high-resolution NMR diffusometry for a series of bis-imidazolium gemini surfactants in aqueous solutions The aggregation behavior in the transition region was studied for a series of dicationic surfactants 3,3'-[alpha,omega-(dioxaalkane)]bis(1-dodecylimidazolium)dichlorides with varied spacer length from two to twelve carbon atoms. We employed Nuclear Magnetic Resonance diffusometry and Bayesian DOSY analysis to obtain the aggregate size distribution in the transition region. The critical concentrations CC were independently obtained from surface tension, electric conductivity, UV-Vis and NMR methods. The micelle aggregation numbers were estimated from the self-diffusion coefficients and were independently confirmed using steady-state fluorescence quenching. The morphology of the aggregates was characterized by small-angle scattering of synchrotron radiation and molecular dynamics simulations. The obtained CC values are identified as critical aggregation concentrations CAC. A broad transition region was observed, and stable micelles were obtained at much higher concentrations than CAC. The accurate CMC values could not be identified for the systems in the study. We indicated that the distribution of aggregate size becomes small and the system becomes homogeneous at much larger concentrations than CAC (typically 15-20 mM). The existence of a slow exchange between two environments, an aggregate and aqueous environment, was confirmed by H-1 NMR and 2D HSQC NMR spectroscopy.

RSC Advances, 8(67), 38470-38482 (2018)

DOI: 10.1039/c8ra07081d   (Pobrane:  2019-03-21)


22.

Chrabąszczewska M., Maszota-Zieleniak M., Pietralik Z., Taube M., Rodziewicz-Motowidło S., Szymańska A., Szutkowski K., Clemens D., Grubb A., Kozak M.

Cyclic trimer of human cystatin C, an amyloidogenic protein - molecular dynamics and experimental studies Human cystatin C (HCC) is a cysteine protease inhibitor that takes a series of oligomeric forms in solution (e.g., dimers, trimers, tetramers, decamers, dodecamers, and other higher oligomers). The best-known form of cystatin C is the dimer, which arises as a result of a domain swapping mechanism. The formation of the HCC oligomeric forms, which is most likely due to this domain swapping mechanism, is associated with the aggregation of HCC into amyloid fibrils and deposits. To investigate the structure of a specific HCC oligomer, we developed a covalently stabilized trimer of HCC. An atomic model of this HCC trimer was proposed on the basis of molecular docking and molecular dynamics simulations. The most stable model of the HCC trimer obtained from the molecular dynamics simulations is characterized by a well-preserved secondary structure. The molecular size and structural parameters of the HCC trimer in solution were also confirmed by Small Angle Neutron Scattering and Nuclear Magnetic Resonance Diffusometry. Published by AIP Publishing.

Journal of Applied Physics, 123(17), Article Number: 174701 (2018)

DOI: 10.1063/1.5023807   (Pobrane:  2019-03-21)


21.

Mrówczyński R., Jędrzak A., Szutkowski K., Grześkowiak B., Coy E., Markiewicz R., Jesionowski T., Jurga S.

Cyclodextrin-based magnetic nanoparticles for cancer therapy Polydopamine (PDA)-coated magnetic nanoparticles functionalized with mono-6-thio-beta-cyclodextrin (SH-beta CD) were obtained and characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Nuclear and Magnetic Resonance Imaging (NMR and MRI), and doxorubicin (DOXO)-loading experiments. The liver cancer cellular internalization of DOXO-loaded nanoparticles was investigated by confocal imaging microscopy. Synthesized nanomaterials bearing a chemotherapeutic drug and a layer of polydopamine capable of absorbing near-infrared light show high performance in the combined chemo- and photothermal therapy (CT-PTT) of liver cancer due to the synergistic effect of both modalities as demonstrated in vitro. Moreover, our material exhibits improved T-2 contrast properties, which have been verified using Carr-Purcell-Meiboom-Gill pulse sequence and MRI Spin-Echo imaging of the nanoparticles dispersed in the agarose gel phantoms. Therefore, the presented results cast new light on the preparation of polydopamine-based magnetic theranostic nanomaterials, as well as on the proper methodology for investigation of magnetic nanoparticles in high field MRI experiments. The prepared material is a robust theranostic nanoasystem with great potential in nanomedicine.

Nanomaterials, 8(3), Article Number: UNSP 170 (2018)

DOI: 10.3390/nano8030170   (Pobrane:  2020-10-23)


20.

Wencka M., Apih T., Korosec R.C., Jenczyk J., Jarek M., Szutkowski K., Jurga S., Dolinsek J.

Molecular dynamics of 1-ethyl-3-methylimidazolium triflate ionic liquid studied by H-1 and F-19 nuclear magnetic resonances The molecular dynamics of an ionic liquid (IL) composed of a 1-ethyl-3-methylimidazolium cation and a triflate (trifluoromethanesulfonate) anion, abbreviated as [Emim][TfO], were studied by NMR spectroscopy. By measuring the temperature-dependent high-field H-1 and F-19 spin-lattice relaxation (SLR) rates, the frequency-dependent H-1 and F-19 SLR dispersion curves using fast-field-cycling relaxometry, and the temperature-dependent H-1 and F-19 diffusion constants, and by utilizing the fact that the primary NMR-active nucleus on the Emim cation is 1H, whereas on the TfO anion it is F-19, the cationic and anionic dynamics were studied separately. A single theoretical relaxation model successfully reproduced all the experimental data of both types of resonant nuclei by fitting all the data simultaneously with the same set of fit parameters. Upon cooling, [Emim][TfO] exhibited a supercooled liquid phase between T-SL = 256 K and the crystallization temperature T-Cr approximate to 227-222 K, as confirmed by differential scanning calorimetry (DSC) experiments. Theoretical analysis revealed that within the liquid and the supercooled liquid states of [Emim][TfO], the H-1 and F-19 relaxation rates are affected by both the rotational and translational diffusional processes with no discontinuous change at TSL. While the rotational diffusion is well described as an Arrhenius thermally activated process, the translational diffusion undergoes strong freezing dynamics that are well described by the Vogel-Fulcher model assuming a freezing temperature of T-0 = 157 K. The existence of the supercooled liquid region in the [Emim][TfO] IL should be taken into account when using this IL for a specific application.

Physical Chemistry Chemical Physics, 19(23), 15368-15376 (2017)

DOI: 10.1039/c7cp01045a


19.

Dobies M., Iżykowska J., Wilkowska M., Woźniak-Braszak A., Szutkowski K., Skrzypczak A., Jurga S., Kozak M.

Dispersion of water proton spin-lattice relaxation rates in aqueous solutions of multiwall carbon nanotubes (MWCNTs) stabilized via alkyloxymethylimidazolium surfactants Carbon nanotubes and a number of other carbon nanomaterials have a tendency to aggregate, which often resulted in difficulties of dispersion of these nanomaterials in aqueous solutions. The ability of dicationic (gemini) surfactants to disperse multiwall carbon nanotubes in water and the dynamic processes taking place at the water-MWCTs interface are studied. Stable dispersions of multi-wall carbon nanotubes with selected gemini surfactants (1,1’-(1,6-hexanediyl)bis(3-alkyloxymethylimidazolium) dichlorides) were prepared and characterized by nuclear magnetic relaxation dispersion (NMRD), NMR diffusometry, scanning and transmission electron microscopy, and Fourier transform infrared spectroscopy. The addition of multiwall carbon nanotubes to aqueous solutions of studied gemini surfactants leads to significant paramagnetic enhancement of the spin-lattice relaxation processes, which gets more pronounced with increasing concentration of well-dispersed MWNTs in water. The dominant role of outer sphere (OS) relaxation mechanism in total observed R1, governed by two-dimensional diffusion of water on the carbon nanotube surface in the vicinity of paramagnetic centers incorporated in the MWCNTs side-walls (mainly of iron origin), was assumed to explain NMRD data. The NMR diffusion experiments confirm the existence of restricted water diffusion in the studied supernatants. The NMR diffusion results are consistent with the FTIR and NMR proton spin-lattice relaxation dispersion in which the more effective R1 dispersion noticed for the sample with IMIC6C12 was ascribed to the better accessibility of water molecules to the surface of the MWCNTs.

The Journal of Physical Chemistry, 121(21), 11839-11850 (2017)

DOI: 10.1021/acs.jpcc.7b01801


18.

Szczeszak A., Ekner-Grzyb A., Runowski M., Szutkowski K., Mrówczyńska L., Kaźmierczak Z., Grzyb T., Dąbrowska K., Giersig M., Lis S.

Spectroscopic, structural and in vitro cytotoxicity evaluation of luminescent, lanthanide doped core@shell nanomaterials GdVO4:Eu(3+)5%@SiO2@NH2 The luminescent GdVO4:Eu(3+)5%@SiO2@NH2 core@shell nanomaterials were obtained via co-precipitation method, followed by hydrolysis and co-condensation of silane derivatives: tetraethyl orthosilicate and 3-aminopropyltriethoxysilane. Their effect on human erythrocytes sedimentation and on proliferation of human lung microvascular endothelial cells was examined and discussed. The luminescent nanopartides were synthesized in the presence of polyacrylic acid or glycerin in order to minimalize the agglomeration and excessive growth of nanostructures. Surface coating with amine functionalized silica shell improved their biocompatibility, facilitated further organic conjugation and protected the internal core. Magnetic measurements revealed an enhanced T-1-relaxivity for the synthesized GdVO4:Eu(3+)5% nanostructures. Structure, morphology and average grain size of the obtained nanomaterials were determined by X-ray diffraction, transmission electron microscopy and dynamic light scattering analysis. The qualitative elemental composition of the nanomaterials was established using energy-dispersive X-ray spectroscopy. The spectroscopic characteristic of red emitting core@shell nanophosphors was completed by measuring luminescence spectra and decays. The emission spectra revealed characteristic bands of Eu3+ ions related to the transitions D-5(0)-F-7(0,1,2,3,4) and D-5(1)-F-7(1). The luminescence lifetimes consisted of two components, associated with the presence of Eu3+ ions located at the surface of the crystallites and in the bulk.

Journal of Colloid and Interface Science, 481, 245-255 (2016)

DOI: 10.1016/j.jcis.2016.07.025   (Pobrane:  2021-01-20)


17.

Adrjanowicz K., Kamiński K., Tarnacka M., Szutkowski K., Popenda Ł., Barbara G., Paluch M.

The effect of hydrogen bonding propensity and enantiomeric composition on the dynamics of supercooled ketoprofen - dielectric, rheological and NMR studies The aim of this work is to analyze in details the role of small hydrogen bonding (HB) structures and enantiomeric composition on the dynamics of glass-forming liquid ketoprofen. For that purpose dielectric relaxation, rheological and NMR studies were performed. Investigated samples are racemic ketoprofen, single enantiomer of ketoprofen and racemic ketoprofen methyl ester with no tendency to form dimeric hydrogen bonding aggregates. Combination of complementary experimental techniques enable us to show that the macroscopic viscosity η and structural relaxation time τα have nearly the same dependencies, whereas the relation between the rotational mobility and translational self-diffusion violates Stokes-Einstein law already at high temperature. Additionally, based on dielectric relaxation studies performed on increased pressure we were able to identify similarities and key differences in the supercooled liquid dynamics of investigated materials affected by their various tendency to form HB cyclic dimers. This includes the effect of pressure on the glass transition temperature Tg, changes in the fragility parameter m and activation volume ΔV, the role of thermal energy and density fluctuations in governing the viscous liquid dynamics (Ev/Ep ratio). Finally, we have also demonstrated that the dynamic behaviour of single enantiomer and racemic mixture of the same compound are very much alike. Nevertheless, some slight differences were observed, particurarly in the τα dependences measured in vinicity of the glass transition both at ambient and elevated pressure.

Physical Chemistry Chemical Physics, 18(15), 10585-10593 (2016)

DOI: 10.1039/C6CP00578K


16.

Sikorska E., Wyrzykowski D., Szutkowski K., Greber K., Lubecka E.A., Zhukov I.

Thermodynamics, size, and dynamics of zwitterionic dodecylphosphocholine and anionic sodium dodecyl sulfate mixed micelles The thermodynamic properties of micellization for dodecylphosphocholine (DPC), sodium dodecyl sulfate (SDS), and their mixtures were studied using isothermal titration calorimetry. NMR relaxation measurements were used to explore molecular mobility of the DPC-containing micelles, whereas the diffusion measurements were taken to determine the micelle size. The DPC/SDS mixed systems reveal a tendency to form two kinds of micelles in buffered solution at lower temperatures. An increase in temperature as well as the transfer of the DPC/SDS mixed micelles from buffered to unbuffered solution results in only a single-step micellization process. The average size of the DPC-containing micelles is only slightly dependent on the SDS fraction. Examination of the data of spin-spin relaxation (T2) shows that methylene protons on the polar headgroup of DPC and methylene protons (H1) on the hydrocarbon chain in the micellar systems studied reveal a heterogeneous dynamic behavior reflected in a two-component T2 relaxation in the whole temperature range. The latter is the main constituent of the rigid interfacial layer core protecting the penetration of water into the hydrophobic interior.

Journal of Thermal Analysis and Calorimetry, 123(1), 511-523 (2016)

DOI: 10.1007/s10973-015-4918-0


15.

Choudhury A.R., Sikorska E., van den Boom J., Bayer P., Popenda Ł., Szutkowski K., Jurga S., Bonomi M., Sali A., Zhukov I., Passamonti S., Novic M.

Structural model of the bilitranslocase transmembrane domain supported by NMR and FRET data We present a 3D model of the four transmembrane (TM) helical regions of bilitranslocase (BTL), a structurally uncharacterized protein that transports organic anions across the cell membrane. The model was computed by considering helix-helix interactions as primary constraints, using Monte Carlo simulations. The interactions between the TM2 and TM3 segments have been confirmed by Forster resonance energy transfer (FRET) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy, increasing our confidence in the model. Several insights into the BTL transport mechanism were obtained by analyzing the model. For example, the observed cis-trans Leu-Pro peptide bond isomerization in the TM3 fragment may indicate a key conformational change during anion transport by BTL. Our structural model of BTL may facilitate further studies, including drug discovery.

PloS ONE, 10(8), e0135455 (2015)

DOI: 10.1371/journal.pone.0135455   (Pobrane:  2020-10-23)


14.

Zhukov I., Choudhury A.R., Sikorska E., Zuperl S., Popenda Ł., Szutkowski K., Novic M., Jurga S.

The FEBS Journal, 281, 647 (2014)


ISSN: 1742-464X   (Pobrane:  2018-03-23)


13.

Gospodarczyk W., Szutkowski K., Kozak M.

Interaction of Bovine Serum Albumin (BSA) with novel gemini surfactants studied by synchrotron radiation scattering (SR-SAXS), circular dichroism (CD) and nuclear magnetic resonance (NMR) The interaction of three dicationic (gemini) surfactants-3,3'-[1,6-(2,5-dioxahexane)]bis(1-dodecylimidazolium) chloride (oxyC2), 3,3'-[1,16-(2,15-dioxahexadecane)]bis(1-dodecylimidazolium) chloride (oxyC12), and 1,4-bis(butane)imidazole-1-yl-3-dodecylimidazolium chloride (C4)-with bovine serum albumin (BSA) has been studied by the use of small-angle X-ray scattering (SAXS), circular dichroism (CD), and H-1 nuclear magnetic resonance diffusometry. The results of CD studies show that the conformation of BSA was changed dramatically in the presence of all studied surfactants. The greater decrease (from 56 to 24%) in the alpha-helical structure of BSA was observed for oxyC2 surfactant. The radii of gyration estimated from SAXS data varied between 3 and 26 nm for the BSA/oxyC2 and BSA/oxyC12 systems. The hydrodynamic radius of the BSA/surfactant system estimated from NMR diffusometry varies between 5 and 11 nm for BSA/oxyC2 and 5 and 8 nm for BSA/oxyC12.

Journal of Physical Chemistry B, 118(29), 8652-8661 (2014)

DOI: 10.1021/jp5047485


12.

Śliwa T., Jarzębski M., Szutkowski K.

Nanoparticle tracking analysis of latex standardized beads The most popular technique for particle size characterization is the dynamic light scattering (DLS). In recent years new advanced method based on counting each single particle movement was introduced giving perspective for measurement of each component of mixture. This study presents some advantages of nanoparticle tracking analysis (NTA) method in comparison to DLS. For tests standard polystyrene beds were chosen vary diameter of 22, 61 and 150 nm and its mixtures. Experiments showed that the particles size resolution allows to distinguish each population in two population suspension opposed to DLS. The NTA method permits to eliminate the negative effects i.e. dust or aggregates in sample during post processing, that permits to use it in a variety of studies.

Current Topics in Biophysics, 37, 49-53 (2014)

DOI: 10.2478/ctb-2014-0074


11.

Jarzębski M., Śliwa T., Jarzębska M., Szutkowski K.

Fabrication of size-tuneable silica particles during seed-growth process The size control is one of the most important factors during seed-growth process. Although precise determination of ingredients concentrations is easily controllable during the growth process, there is still a possibility to synthesize oversized particles. Nanosized fluorescent silica particles were synthetized using Stöber process and verified using three complementary methods of particle size determination, namely Dynamic Light Scattering (DLS), Particle Tracking (PT) as well as by Transmission Electron Microscopy (TEM) and Confocal Microscopy. The final diameter was verified by DLS and estimated to 494 nm. Parameters necessary to control the size were derived.

Current Topics in Biophysics, 37, 35-41 (2014)

DOI: 10.2478/ctb-2014-0072


10.

Murawska M., Wiatr M., Nowakowski P., Szutkowski K., Skrzypczak A., Kozak M.

The structure and morphology of gold nanoparticles produced in cationic gemini surfactant systems Potential applications of gold nanoparticles (GNP) are strictly connected with their size and shape. The influence of different dicationic (gemini) surfactants, alkyloxymethylimidazolium derivatives derivatives, on the structure and morphology of GNP was studied. The synthesis of nanoparticles was performed in the presence of various gemini surfactants-dodecyloxymethylimidazolium nitrate (IMI_NO3_C4_C12), propionate (IMI_PROP_C4_C12) and 3,3'-[1,9-(2,8-dioxanonane)]bis-(1-nonyloxymethylimidazolium) chloride (IMI_Cl_oxyC7_C9), used as stabilizers and templates for obtaining different size and shape of gold nanoparticles. The samples obtained were examined using transmission electron microscopy (TEM), small angle scattering of synchrotron radiation (SAXS), UV-vis spectroscopy and NMR PFG spectroscopy. For the obtained solutions of nanoparticles the plasmon resonance was observed at the wavelengths corresponding to the presence of gold nanoparticles of sizes ranging from 5-100 nm, with a significant shift towards higher wavelength for the samples prepared with addition of dicationic surfactants. TEM images evidence the presence of gold nanoparticles with tetrahedral and spherical morphology in solutions prepared with the surfactants IMI_PROP_C4_C12, IMI_NO3_C4_C12, and those of spherical morphology, but strongly aggregated, in the solution with the cationic surfactant IMI_Cl_oxyC7_C9.
(C) 2013 Elsevier Ltd. All rights reserved.

Radiation Physics and Chemistry, 93, 160-167 (2013)

DOI: 10.1016/j.radphyschem.2013.05.024


9.

Strankowska J., Piszczyk L., Strankowski M., Danowska M., Szutkowski K., Jurga S., Kwela J.

Molecular dynamics studies of polyurethane nanocomposite hydrogels Polyurethane PEO-based hydrogels have a broad range of biomedical applicability. They are attractive for drug-controlled delivery systems, surgical implants and wound healing dressings. In this study, a PEO based polyurethane hydrogels containing CloisiteA (R) 30B, an organically modified clay mineral, was synthesized. Structure of nanocomposite hydrogels was determined using XRD technique. Its molecular dynamics was studied by means of NMR spectroscopy, DMA and DSC analysis. The mechanical properties and thermal stability of the systems were improved by incorporation of clay and controlled by varying the clay content in polymeric matrix. Molecular dynamics of polymer chains depends on interaction of CloisiteA (R) 30B nanoparticles with soft segments of polyurethanes. The characteristic nanosize effect is observed.

European Physical Journal - Special Topics, 222(9), 2179-2186 (2013)

DOI: 10.1140/epjst/e2013-01994-8


8.

Makrocka-Rydzyk M., Wegner K., Szutkowski K., Kozak M., Jurga S., Gao H.

Morphology and NMR self-diffusion in PBA/PEO miktoarm star copolymers Morphology and NMR self-diffusion of two miktoarm star copolymers differing in fraction of poly(n-butyl acrylate) and poly(ethylene oxide) (PBA and PEO) arms were under investigation. Structural characteristics of copolymers was obtained on the basis of Small Angle X-Ray Scattering (SAXS) investigations. The phase separated nanoscale morphology of the miktoarm star copolymer with a high fraction of PEO arms was confirmed by Scanning Probe Microscopy (SPM) studies. The modified Avrami approach was used to obtain the information on the non-isothermal crystallization kinetics of the studied systems. It was observed that the crystallization in the system with a higher content of PBA, occurring at higher undercooling, was characterized by a higher crystallization rate. It was also found that increase in PBA arms fraction leads to the reduction in the size of PEO domains. The activation energy of the crystallization process, estimated with Kissinger's method, is lower for miktoarm star copolymer with higher PBA content, which results from facilitation of the transport of PEO chains in the direction of the growing crystal due to the presence of mobile PBA arms. The self-diffusion studies of miktoarm star copolymers melts, carried out with the Pulsed-Gradient STimulated-Echo (PGSTE) Nuclear Magnetic Resonance (NMR) technique, reveals the existence of at least two types of diffusion mechanisms in these systems.

Zeitschrift für Physikalische Chemie, 226, 1271-1292 (2012)

DOI: 10.1524/zpch.2012.0300   (Pobrane:  2020-10-23)


7.

Szutkowski K., Jurga S.

Long-range ordering in lyotropic lamellar phase studied by high resolution MR diffusion-weighted imaging Diffusion-weighted magnetic resonance imaging (DW MRI) was applied to the lyotropic lamellar phase of the dodecylammonium chloride/water system (DDACl/H(2)O). In the course of employing a well-known medical imaging method, namely, diffusion tensor imaging (DTI), the system morphology was assessed accurately ill the most straightforward way by two-dimensional visualization of eigenvectors associated with planar distribution of effective diffusion tensors throughout the whole slice with 40 mu m in-plane resolution. Long-range order was observed in the Studied lamellar phase, and morphology was best described by a combination of three- and one-dimensional diffusion.

The Journal of Physical Chemistry B, 114(1), 165-173 (2010)

DOI: 10.1021/jp9072087


6.

Dvinskikh S.V., Szutkowski K., Petrov O.V., Furó I.

Abstrakt lub materiały konferencyjne, albo abstrakt publikacji
z dodatkowymi numerami DOI

NMR imaging and cryoporometry of swelling clays Compacted bentonite clay is currently attracting attention as a promising “self-sealing” buffer material to build in-ground barriers for the encapsulation of radioactive waste. It is expected to fill up the space between waste canister and surrounding ground by swelling and thus delay flow and migration from the host rock to the canister. In environmental sciences, evaluation and understanding of the swelling properties of pre-compacted clay are of uttermost importance for designing such buffers. Major goal of present study was to provide, in a non-invasive manner, a quantitative measure of bentonite distribution in extended samples during different physical processes in an aqueous environment such as swelling, dissolution, and sedimentation on the time scale from minutes to years. The propagation of the swelling front during clay expansion depending on the geometry of the confining space was also studied. Magnetic resonance imaging and nuclear magnetic resonance spectroscopy were adapted and used as main experimental techniques. With this approach, spatially resolved movement of the clay/water interface as well as clay particle distributions in gel phase can be monitored [1]. Bulk samples with swelling in a vertical tube and in a horizontal channel were investigated and clay content distribution profiles in the concentration range over five orders of magnitude and with sub-millimetre spatial resolution were obtained. Expansion rates for bulk swelling and swelling in narrow slits were compared. For sodium-exchanged montmorillonite in contact with de-ionised water, we observed a remarkable acceleration of expansion as compared to that obtained in the bulk. To characterize the porosity of the clay a cryoporometric study [2] has been performed. Our results have important implications to waste repository designs and for the assessment of its long-term performance. Further research exploring clay-water interaction over a wide variety of clay composition and water ionic strength as well as investigating the effect of the confining geometry and material surface properties seem to be worth to pursue.

Geophysical Research Abstracts, 12, EGU2010-15180 (2010)


5.

Dvinskikh S.V., Szutkowski K., Furó I.

MRI profiles over a very wide concentration ranges: application to swelling of a bentonite clay In MRI investigation of soils, clays, and rocks, mainly mobile water is detected, similarly to that in biological and medical samples. However, the spin relaxation properties of water in these materials and/or low water concentration may make it difficult to use standard MRI approaches. Despite these limitations, one can combine MRI techniques developed for solid and liquid states and use independent information on relaxation properties of water, interacting with the material of interest, to obtain true images of both water and material content. We present procedures for obtaining such true density maps and demonstrate their use for studying the swelling of bentonite clay by water. A constant time imaging protocol provides 1D mapping of the clay distribution in regions with clay concentration above 10 vol%. T(1) relaxation time imaging is employed to monitor the clay content down to 10(-3) vol%. Data provided by those two approaches are in good agreement in the overlapping range of concentrations. Covering five orders of magnitude of clay concentration, swelling of sodium-exchanged bentonite clays from pre-compacted pellets into a gel phase is followed in detail.
(C) 2009 Elsevier Inc. All rights reserved.

Journal of Magnetic Resonance, 198(2), 146-150 (2009)

DOI: 10.1016/j.jmr.2009.01.035


4.

Szutkowski K., Furo I.

Effective and accurate single-shot NMR diffusion experiments based on magnetization grating Current single-shot diffusion methods based on magnetization gratings suffer from low sensitivity due to small rf tip angles and, consequently, from inefficient use of the total equilibrium magnetization. Here, we propose and illustrate the use of a slightly modified form of the magnetization encoding scheme OUFIS for single-shot diffusion experiments. In a detailed theoretical and experimental analysis, we compare the performance of the proposed method to other encoding schemes such as the one-phase or two-phase DANTE and conclude that the OUFIS-based experiment is a superior one. The primary reason is that this scheme allows one to use a larger total pulse area. Hence, one can encode a far larger portion of the initial magnetization into a frequency grating before the onset of various nonlinear effects. In the experimental illustration, we present a single-shot measurement of multicomponent diffusion.
(C) 2008 Elsevier Inc. All rights reserved.

Journal of Magnetic Resonance, 195(2), 123-128 (2008)

DOI: 10.1016/j.jmr.2008.08.009   (Pobrane:  2020-10-21)


3.

Szutkowski K., Stilbs P., Jurga S.

Proton chemical exchange in aqueous solutions of dodecylammonium chloride: Effects of micellar aggregation Proton chemical exchange was studied in aqueous solutions of dodecylammonium chloride (DDAC1) for two selected concentrations, 18 and 33 wt %. The Fourier transform Carr-Pureell-Meiboom-Gill (CPMG) NMR method combined with the Carver and Richards model for T-2 dispersion curve analysis were employed to evaluate the temperature dependence of the proton exchange rates k(ex). An increase of the energy barrier height Delta G double dagger for the proton chemical exchange between water and ammonium cation (-NH3+) was observed as the DDAC1 concentration was increased. Results are complementary to previous studies of aggregation phenomena for various n-alkylammonium chlorides.

Journal of Physical Chemistry C, 111(43), 15613-15619 (2007)

DOI: 10.1021/jp073696s   (Pobrane:  2020-10-23)


2.

Szutkowski K., Klinowski J., Jurga S.

NMR studies of restricted diffusion in lyotropic systems Tortuosity, 1/alpha, and surface-to-volume ratio, S/V, were determined in aqueous solutions of decylammonium, dodecylammonium and tetradecylammonium chlorides of various concentrations by measuring the apparent diffusion coefficient of water, D-app(Delta). This was found to be much smaller than in the bulk state. Such restricted diffusion is interpreted in terms of the Mitra model, where D(A) depends on diffusion time and is controlled primarily by S/V. The samples exhibit lamellar (L), hexagonal (H) and isotropic (1) liquid crystalline phases. We observed changes in S/V upon phase transition. In the lamellar and hexagonal phases, the system is ordered, resulting in relatively small S/V ratios, compared to the micellar-isotropic phase. We did not observe a dependence on the diffusion time, A, in the isotropic phase, because the duration of the experiment was not sufficiently short to observe the change from Dapp(A) to Den. We observed the effective diffusion coefficient of water, which directly probes the tortuosity of the system. The S/V ratios were obtained by fitting the Mitra model, using known values of the bulk water diffusion coefficients, and the assumption that D-app --> D-0 for Delta --> 0. S/V is correlated with the type of structure, increasing on transition to the isotropic phase and decreasing on transition to other phases. The change in tortuosity is small, but slightly larger for the isotropic phase.
(C) 2002 Elsevier Science (USA).

Solid State Nuclear Magnetic Resonance, 22(2-3), 394-408 (2002)

DOI: 10.1006/snmr.2002.0087   (Pobrane:  2020-10-21)


1.

Szutkowski K., Jurga S.

NMR study of restricted diffusion in lyotropic systems We present NMR diffusion measurements of n-alkyl ammonium salts-water systems (with n = 10, 12, 14) in their isotropic, lamellar and hexagonal liquid crystalline phases. Our experimental data are explained in terms of non-restricted and restricted diffusion of water molecules. Using the model of Mitra for restricted diffusion of molecules we were able to determine the Surface to Volume Ratios in lamellar phases, which were decreasing with increasing temperature.

Molecular Physics Reports, 33, 179-183 (2001)

WWW: http://www.ifmpan.poznan.pl/mol/
ISSN: 1502-1250   (Pobrane:  2021-01-07)


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