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This work explores what Fast Field-Cycling Nuclear Magnetic Resonance (FFC-NMR) relaxometry brings for the study of sarcoma to guide future in vivo analyses of patients. We present the results of an ex vivo pilot study involving 10 cases of biopsy-proven sarcoma and we propose a quantitative method to analyse 1H NMR relaxation dispersion profiles based on a model-free approach describing the main dynamical processes in the tissues and assessing the amplitude of the Quadrupole Relaxation Enhancement effects due to 14N. This approach showed five distinct groups of dispersion profiles indicating five discrete categories of sarcoma, with differences attributable to microstructure and rigidity. Data from tissues surrounding sarcomas indicated very significant variations with the proximity to tumour, which may be attributed to varying water content but also to tissue remodelling processes due to the sarcoma. This pilot study illustrates the potential of FFC relaxometry for the detection and characterisation of sarcoma.

1H spin-lattice relaxation experiments have been performed for a series of ionic liquids including bis(trifluoromethanesulfonyl)imide anion and cations of a varying alkyl chain length: triethylhexylammonium, triethyloctylammonium, decyltriethylammonium, dodecyltriethylammonium, triethyltetradecylammonium, and hexadecyltriethylammonium. The relaxation studies were carried out in abroad frequency range covering three orders of magnitude, from 10 kHz to 10 MHz, versus temperature. On the basis of a thorough, quantitative analysis of this reach data set, parameters characterizing the relative, cation-cation, translation diffusion (relative diffusion coefficients and translational correlation times), and rotational motion of the cation (rotational correlation times) were determined. Relationships between these quantities and their dependence on the alkyl chain length were discussed in comparison to analogous properties of molecular liquids. It was shown, among other findings, that the ratio between the translational and rotational correlation times is smaller than for molecular liquids and considerably dependent on temperature. Moreover, a comparison of relative and self-diffusion coefficients indicate correlated translational dynamics of the cations.

1H spin−lattice nuclear magnetic resonance relaxation experiments were performed for five kinds of dermal fillers based on hyaluronic acid. The relaxation data were collected over a broad frequency range between 4 kHz and 40 MHz, at body temperature. Thanks to the frequency range encompassing four orders of magnitude, the dynamics of water confined in the polymeric matrix was revealed. It is demonstrated that translation diffusion of the confined water molecules exhibits a two‐dimensional character and the diffusion process is slower than diffusion in bulk water by 3–4 orders of magnitude. As far as rotational dynamics of the confined water is concerned, it is shown that in all cases there is a water pool characterized by a rotational correlation time of about 4×10−9 s. In some of the dermal fillers a fraction of the confined water (about 10 %) forms a pool that exhibits considerably slower (by an order of magnitude) rotational dynamics. In addition, the water binding capacity of the dermal fillers was quantitatively compared., Mechanism of water diffusion: Profiting from the potential of NMR relaxometry to reveal mechanism of molecular motion in condensed matter, we demonstrate the 2D character of the translation diffusion of water in hyaluronic acid gels. The diffusion process is slower than diffusion in bulk water by 3–4 orders of magnitude.

1H spin-lattice relaxation experiments for gelatin-based candies prepared by different amounts of d -allulose have been performed in the frequency range of 4 kHz–40 MHz. In addition, physical properties such as moisture content and hardness were also measured. Analysis of NMR dispersion profiles showed the presence of two fractions of water: confined and free-water. The relaxation data have been associated with parameters characterizing translation diffusion and rotation of the confined-water molecules and dynamics of the free-water fraction. The translation dynamics has turned out to be about three orders of magnitude slower compared to bulk water; the time scale of the rotational dynamics is similar to that of translation diffusion. Moreover, quantitative analysis of the relaxation data has provided a unique parameter, the number of water molecules undergoing translation dynamics within the confined-water fraction per unit volume. On this basis, the influence of d -allulose on the mechanisms of water motion has been discussed.

1H Nuclear Magnetic Resonance relaxometry studies have been performed for fifteen kinds of oil. The measurements of 1H spin-lattice relaxation rates have been carried out in a frequency range encompassing three orders of magnitude: from about 10 kHz to 10 MHz, at room temperature. The data have been analysed in terms of a rigorous model rendering translation diffusion coefficients and providing some insight into rotational dynamics of triacylglycerols molecules. It has been observed that the diffusion is approximately by about 200 times slower compared to water diffusion in bulk and the diffusion coefficient varies in a narrow range. The diffusion coefficients have been combined with viscosity for different kinds of oil. A relationship between the molecular (the diffusion coefficient) and macroscopic (the viscosity coefficient) quantities have been established. It has turned out that most of oils follows the revealed relation. Discrepancies from the relationship, observed for some oils, have been discussed.

1H spin-lattice relaxation studies of different kinds of honey have been performed in a broad frequency range, versus temperature. On the basis of the extensive data set, translation diffusion coefficients and rotational correlation times of water molecules confined in the sugar matrix have been determined. It has turned out that the translation dynamics is of three-dimensional (isotropic) character and its by three orders of magnitude slower compared to water in bulk. This scenario established on the molecular level has been compared with the picture of translation diffusion obtained from viscosity measurements. Systematic discrepancies have been observed for all kinds of honey and their origin has been explained. Activation energies of the translational and rotational motion and ratios between the translational and rotational correlational times have been determined and discussed in the context of the properties of supercooled liquids.

1H spin–lattice relaxation studies of water solutions of Bismuth-ethylenediamine-tetraacetic acid (Bi- EDTA), Bismuth-ethylenediamine-tetrakis(methylenephosphonic) acid (Bi-EDTP), Bismuth-1,4,7,10- tetraazacyclododecane-1,4,7,10-tetraacetic acid (Bi-DOTA), Bismuth-1,4,7,10-tetraazacyclodo decane-1,4,7,10-tetrakis(methylenephosphonic acid) (Bi-DOTP) and Bismuth-1,4,7,10-tetraazacyclo dodecane-1,4,7-triacetic acid (Bi-DO3A) have been performed in order to compare Quadrupole Relaxation Enhancement (QRE) effects with Paramagnetic Relaxation Enhancement (PRE) from the perspective of exploiting the first one as a novel contrast mechanism for Magnetic Resonance Imag- ing (MRI). The selected compounds can be considered as 209Bi counterparts of Gd3+ complexes. The relaxation experiments havebeenperformed in a broad frequency range of5 kHz–30 MHz.Therelax- ation contribution associated with QRE has been extracted from the data and compared with PRE. Similarities and differences between the two effects have been discussed.

H-1 spin-lattice relaxation experiments have been performed for triphenylbismuth dissolved in fully deuterated glycerol and tetrahydrofuran. The experiments have been carried out in a broad frequency range, from 10kHz to 40MHz, versus temperature. The data have been analysed in terms of a relaxation model including two relaxation pathways: H-1-H-1 dipole-dipole interactions between intrinsic protons of triphenylbismuth molecule and H-1-H-2 dipole-dipole interactions between the solvent and solute molecules. As a result of the analysis, rotational correlation times of triphenylbismuth molecules in the solutions and relative translational diffusion coefficient between the solvent and solute molecules have been determined. Moreover, the role of the intramolecular H-1-H-1 relaxation contribution has been revealed, depending on the motional parameters, as a result of decomposing the overall relaxation dispersion profile into contributions associated with the H-1-H-1 and H-1-H-2 relaxation pathways. The possibility of accessing the contribution of the relaxation of the intrinsic protons is important from the perspective of exploiting Quadrupole Relaxation Enhancement effects as possible contrast mechanisms for Magnetic Resonance Imaging.

Magnetic Resonance Imaging (MRI) is one of the most powerful diagnostic tools providing maps of 1H relaxation times of human body. The method needs, however, a contrast mechanism to enlarge the difference in the relaxation times between healthy and pathological tissues. In this work we discuss the potential of a novel contrast mechanism for MRI, based on Quadrupole Relaxation Enhancement (QRE) and estimate the achievable value of QRE under the most favorable conditions. It has turned out that the theoreticaly possible enhancement factors are smaller than those of typical paramagnetic contrast agents but in turn the field-selectivity of QRE-based agents makes them extremely sensitive to subtle changes of the electric field gradient in the tissue. So far QRE has been observed for solids (in most cases for 14N) as a result of very slow dynamics and anisotropic spin interactions, believed to be necessary for QRE to appear. We show the first evidence that QRE can be achieved in solutions of compounds containing a high spin nucleus (209Bi) as the quadrupole element. The finding of QRE in liquid state is explained in terms of spin relaxation theory based on the stochastic Liouville equation. The results confirm the relaxation theory and motivate further exploration of the potential of QRE for MRI., The original publication can be found at: https://doi.org/10.1063/1.5082177

H-1 spin-lattice nuclear magnetic resonance relaxation experiments have been performed for triphenylbismuth dichloride (C18H15BiCl2) and phenylbismuth dichloride (C6H5BiCl2) in powder. The frequency range of 20-128 MHz has been covered. Due to H-1-Bi-209 dipole-dipole interactions, a rich set of pronounced Quadrupole Relaxation Enhancement (QRE) peaks (quadrupole peaks) has been observed. The QRE patterns for both compounds have been explained in terms of single- and double-quantum transitions of the participating nuclei. The analysis has revealed a complex, quantum-mechanical mechanism of the QRE effects. The mechanism goes far beyond the simple explanation of the existence of three quadrupole peaks for N-14 reported in literature. The analysis has been supported by nuclear quadrupole resonance results that independently provided the Bi-209 quadrupole parameters (amplitude of the quadrupole coupling constant and asymmetry parameter).

1H NMR relaxometry studies have been performed for different kinds of cheese in order to enquire into mechanisms of water mobility in the cheese structures. The exploited frequency range, from 4 kHz to 40 MHz, allowed probing water dynamics on a broad range of time scales. Two fractions of water of much different dynamical properties, referred to as confined-water and free-water, have been revealed. It has been demonstrated that dynamics of water molecules confined in the macromolecular matrix is about four orders of magnitude slower compared to bulk water, while the second fraction exhibits dynamics by slower only by one order of magnitude. It has turned out that the differences in the water behaviour and, hence, macroscopic properties of cheese are related to differences in the relative populations of these fractions and the portion of water molecules bound to proteins, while the time scale of water dynamics is similar for all cases.

1H spin-lattice relaxation studies have been performed for pure [Bi(NO3)3(H2O)3]*18-crown-6 in powder and its solution in dimethyl sulfoxide (DMSO). The experiments have been carried out in the frequency range of 10 kHz–30MHz and the temperature range of 240–277 K; at 277 K the solution is already frozen. The 1Hrelaxation of pure [Bi(NO3)3(H2O)3]*18-crown-6 has been interpreted in terms of three dynamical processes. Quadrupole Relaxation Enhancement effects have been observed in the frozen DMSO solution of [Bi(NO3)3(H2O)3]*18-crown-6. The specific mechanisms of the 1H spin- lattice relaxation enhancement have been discussed distinguishing between effects caused by time independent (residual) and fluctuating 1H-209Bi dipole-dipole interactions.

We propose a simple method to calculate and predict quadrupole relaxation enhancement (QRE) features in the spin-lattice nuclear magnetic relaxation dispersion (R1-NMRD) profile of protons (1H) in solids. The only requirement is the knowledge of the nuclear quadrupole resonance (NQR) parameters of the quadrupole nuclei in a molecule. These NQR parameters – the quadrupole coupling constant Qcc and the asymmetry parameter η – can be determined by NQR spectroscopy or using quantum chemistry calculations. As there is an increasing interest in using molecules producing high field QRE features as, e.g. for contrast enhancing agents in magnetic resonance imaging, the experimental efforts of seeking for suitable compounds can be reduced by pre-selecting molecules via calculations. Also, the method can be used to extract NQR parameter, and thus structural information, from R1-NMRD profiles showing QRE features. In this article, we describe the calculation procedure and present examples of comparing the result to experimental R1-NMRD data of two different solid 209Bi-aryl compounds.

Motivated by the possibility of exploiting species containing high spin quantum number nuclei (referred to as quadrupole nuclei) as novel contrast agents for Magnetic Resonance Imaging, based on Quadrupole Relaxation Enhancement (QRE) effects, 1H spin–lattice relaxation has been investigated for tris(2-methoxyphenyl)bismuthane and tris(2,6-dimethoxyphenyl)bismuthane in powder. The relaxation experiment has been performed in the magnetic field range of 0.5 T to 3 T (the upper limit corresponds to the field used in many medical scanners). A very rich QRE pattern (several frequency specific 1H spin–lattice relaxation rate maxima) has been observed for both compounds. Complementary Nuclear Quadrupole Resonance experiments have been performed in order to determine the quadrupole parameters (quadrupole coupling constant and asymmetry parameters) for 209Bi. Knowing the parameters, the QRE pattern has been explained on the basis of a quantum-mechanical picture of the system including single and double-quantum coherences for the participating nuclei (1H and 209Bi). In this way the quantum-mechanical origin of the spin transitions leading to the QRE effects has been explained.

In this paper the molecular dynamics of a common local-anesthetic drug, lidocaine hydrochloride (LD-HCl), and its water mixtures were investigated. By means of broadband dielectric spectroscopy and calorimetric measurements it was shown that even a small addition of water causes a significant effect on the relaxation dynamics of analyzed protic ionic liquid. Apart from the two well-resolved relaxations (σ- and γ-processes) and the β-mode, identified as the JG-process, observed for anhydrous LD-HCl, a new relaxation peak (υ) is visible in the dielectric spectra of aqueous mixtures of this drug. Additionally, the significant effect of the water on the glass transition temperature of LD-HCl was found. The sample characterized with mole fraction of water X(w) = 0.44 reveals the glass transition temperature T(g), 42 K lower than that of anhydrous material (307 K). Finally, it was shown that by amorphization of the hydrochloride salt of lidocaine it is possible to obtain its room temperature ionic liquid form.

In this paper, we consider the glass transition as a kinetic process and establish one universal equation for the pressure coefficient of the glass transition temperature, dTg/dp, which is a thermodynamic characteristic of this process. Our findings challenge the common previous expectations concerning key characteristics of the transformation from the liquid to the glassy state, because it suggests that without employing an additional condition, met in the glass transition, derivation of the two independent equations for dTg/dp is not possible. Hence, the relation among the thermodynamic coefficients, which could be equivalent to the well-known Prigogine-Defay ratio for the process under consideration, cannot be obtained. Besides, by comparing the predictions of our universal equation for dTg/dp and Ehrenfest equations, we find the aforementioned supplementary restriction, which must be met to use the Prigogine-Defay ratio for the glass transition.

To solve a long-standing problem of condensed matter physics with determining a proper description of the thermodynamic evolution of the time scale of molecular dynamics near the glass transition, we have extended the well-known Adam-Gibbs model to describe the temperature-volume dependence of structural relaxation times, τα(T, V). We also employ the thermodynamic scaling idea reflected in the density scaling power law, τα = f(T−1V−γ), recently acknowledged as a valid unifying concept in the glass transition physics, to differentiate between physically relevant and irrelevant attempts at formulating the temperature-volume representations of the Adam-Gibbs model. As a consequence, we determine a straightforward relation between the structural relaxation time τα and the configurational entropy SC, giving evidence that also SC(T, V) = g(T−1V−γ) with the exponent γ that enables to scale τα(T, V). This important findings have meaningful implications for the connection between thermodynamics and molecular dynamics near the glass transition, because it implies that τα can be scaled with SC.

In this Letter, an entropic model recently formulated by Mauro et al. for the temperature dependence of viscosity in glass-forming materials is generalized to describe the temperature-volume dependences of viscosities and structural relaxation times near the glass transition. It is found that the generalization shows limitations of its temperature precursor. The extended model describes well the structural dielectric relaxation times τα(T,V) of supercooled van der Waals liquids. The obtained results are discussed in the context of the thermodynamic scaling law for molecular dynamics of viscous systems.

The fragility parameter has been acknowledged as one of the most important characteristics of glass-forming liquids. We show that the mystery of the dramatic change in molecular dynamics of systems approaching the glass transition can be better understood by the high pressure study of fragility parameters defined in different thermodynamic conditions. We formulate and experimentally confirm a few rules obeyed by the fragility parameters, which are also rationalized by the density scaling law and its modification suggested for associated liquids. In this way, we successfully explore and gain a new insight into the pressure effect on molecular dynamics of van der Waals liquids, polymer melts, ionic liquids, and hydrogen-bonded systems near the glass transition.

Motivated by the possibility of exploiting species containing high spin quantum number nuclei (referred to as quadrupole nuclei) as novel contrast agents for Magnetic Resonance Imaging, based on Quadrupole Relaxation Enhancement (QRE) effects, H-1 spin-lattice relaxation has been investigated for tris(2-methoxyphenyl) bismuthane and tris(2,6-dimethoxyphenyl) bismuthane in powder. The relaxation experiment has been performed in the magnetic field range of 0.5 T to 3 T (the upper limit corresponds to the field used in many medical scanners). A very rich QRE pattern (several frequency specific H-1 spin-lattice relaxation rate maxima) has been observed for both compounds. Complementary Nuclear Quadrupole Resonance experiments have been performed in order to determine the quadrupole parameters (quadrupole coupling constant and asymmetry parameters) for Bi-209. Knowing the parameters, the QRE pattern has been explained on the basis of a quantum-mechanical picture of the system including single and double-quantum coherences for the participating nuclei (H-1 and Bi-209). In this way the quantum-mechanical origin of the spin transitions leading to the QRE effects has been explained.

Motivated by the possibility of exploiting species containing high spin quantum number nuclei (referred to as quadrupole nuclei) as novel contrast agents for Magnetic Resonance Imaging, based on Quadrupole Relaxation Enhancement (QRE) effects, 1H spin-lattice relaxation has been investigated for tris(2-methoxyphenyl)bismuthane and tris(2,6- dimethoxyphenyl)bismuthane in powder. The relaxation experiment has been performed in the magnetic field range of 0.5 T to 3 T (the upper limit corresponds to the field used in many medical scanners). A very rich QRE pattern (several frequency specific 1H spin-lattice relaxation rate maxima) has been observed for both compounds. Complementary Nuclear Quadrupole Resonance experiments have been performed in order to determine the quadrupole parameters (quadrupole coupling constant and asymmetry parameters) for 209Bi. Knowing the parameters, the QRE pattern has been explained on the basis of a quantummechanical picture of the system including single and double-quantum coherences for the participating nuclei (1H and 209Bi). In this way the quantum-mechanical origin of the spintransitions leading to the QRE effects has been explained.

Motivated by the possibility of exploiting species containing high spin quantum number nuclei (referred to as quadrupole nuclei) as novel contrast agents for Magnetic Resonance Imaging, based on Quadrupole Relaxation Enhancement (QRE) effects, 1H spin-lattice relaxation has been investigated for tris(2-methoxyphenyl)bismuthane and tris(2,6- dimethoxyphenyl)bismuthane in powder. The relaxation experiment has been performed in the magnetic field range of 0.5 T to 3 T (the upper limit corresponds to the field used in many medical scanners). A very rich QRE pattern (several frequency specific 1H spin-lattice relaxation rate maxima) has been observed for both compounds. Complementary Nuclear Quadrupole Resonance experiments have been performed in order to determine the quadrupole parameters (quadrupole coupling constant and asymmetry parameters) for 209Bi. Knowing the parameters, the QRE pattern has been explained on the basis of a quantummechanical picture of the system including single and double-quantum coherences for the participating nuclei (1H and 209Bi). In this way the quantum-mechanical origin of the spintransitions leading to the QRE effects has been explained.

1H and 19F spin-lattice relaxation experiments have been performed for butyltriethylammonium bis(trifluoromethanesulfonyl)imide in the temperature range from 258 to 298 K and the frequency range from 10 kHz to 10 MHz. The results have thoroughly been analysed in terms of a relaxation model taking into account relaxation pathways associated with 1H–1H, 19F–19F and 1H–19F dipole–dipole interactions, rendering relative translational diffusion coefficients for the pairs of ions: cation–cation, anion–anion and cation–anion, as well as the rotational correlation time of the cation. The relevance of the 1H–19F relaxation contribution to the 1H and 19F relaxation has been demonstrated. A comparison of the diffusion coefficients has revealed correlation effects in the relative cation–anion translational movement. It has also turned out that the translational movement of the anions is faster than of cations, especially at high temperatures. Moreover, the relative cation–cation diffusion coefficients have been compared with self-diffusion coefficients obtained by means of NMR (Nuclear Magnetic Resonance) gradient diffusometry. The comparison indicates correlation effects in the relative cation–cation translational dynamics—the effects become more pronounced with decreasing temperature.

1H Nuclear Magnetic Resonance (NMR) relaxometry and Dielectric Spectroscopy (DS) have been exploited to investigate the dynamics of solid proteins. The experiments have been carried out in the frequency range of about 10 kHz-40 MHz for NMR relaxometry and 10−2Hz-20 MHz for DS. The data sets have been analyzed in terms of theoretical models allowing for a comparison of the correlation times revealed by NMR relaxometry and DS. The 1H spin–lattice relaxation profiles have been decomposed into relaxation contributions associated with 1H–1H and 1H-14N dipole – dipole interactions. The 1H–1H relaxation contribution has been interpreted in terms of three dynamical processes of time scales of 10−6s, 10−7s and 10−8s. It has turned out that the correlation times do not differ much among proteins and they are only weakly dependent on temperature. The analysis of DS relaxation spectra has also revealed three motional processes characterized by correlation times that considerably depend on temperature in contrast to those obtained from the 1H relaxation. This finding suggest that for solid proteins there is a contribution to the 1H spin–lattice relaxation associated with a kind of motion that is not probed in DS as it does not lead to a reorientation of the electric dipole moment.