Prussian blue type nanoparticles are exciting nano-objects that combine the advantages of molecule-based materials and nanochemistry. Here we provide a short overview focalizing on the recent ...advances of these nano-objects designed for biomedical applications and give an outlook on the future research orientations in this domain.
Recent developments in the field of Prussian blue-type nanomaterials for biomedical applications.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
3.
First cage-like pentanuclear Co(ii)-silsesquioxane Bilyachenko, A N; Yalymov, A I; Levitsky, M M ...
Dalton transactions : an international journal of inorganic chemistry,
01/2016, Volume:
45, Issue:
35
Journal Article
Peer reviewed
A new pentanuclear "cylinder"-like cobalt(ii) phenylsilsesquioxane (PhSiO1.5)10(CoO)5(NaOH) exhibits a slow relaxation of the magnetization and a high catalytic activity and stereoselectivity in the ...oxidation of alkanes and alcohols.
Cyano-bridged Gd(3+)/Fe(CN)6(3-) coordination polymer nanoparticles of 3-4 nm stabilized with D-mannitol presenting a high r1 relaxivity value of 11.4 mM(-1) s(-1) were investigated in vivo as ...contrast agents (CA) for Magnetic Resonance Imaging (MRI). They allow an increase of the MR image contrast and can act as an efficient intravascular T1 CA with a relatively long blood-circulation lifetime (60 min) without specific toxicity.
Prussian blue (PB) and its analogues on the nanometric scale are exciting nano-objects that combine the advantages of molecular-based materials and nanochemistry. Herein, we demonstrate that ...ultra-small PB nanoparticles of 2-3 nm can be easily labelled with radioactive (201)Tl(+) to obtain new nanoprobes as radiotracers for 201-thallium-based imaging.
We present a systematic experimental comparison of the superparamagnetic relaxation time constants obtained by means of dynamic magnetic measurements and 1H-NMR relaxometry, on ferrite-based ...nanosystems with different composition, various core sizes and dispersed in different solvents. The application of a heuristic model for the relaxivity allowed a comparison between the reversal time of magnetization as seen by NMR and the results from the AC susceptibility experiments, and an estimation of fundamental microscopic properties. A good agreement between the NMR and AC results was found when fitting the AC data to a Vogel-Fulcher law. Key parameters obtained from the model have been exploited to evaluate the impact of the contribution from magnetic anisotropy to the relaxivity curves and estimate the minimum approach distance of the bulk solvent.
In this paper, we report the synthesis of size-controlled (6 and 18nm) monodisperse magnetic iron oxide nanoparticles, from the pyrolysis of iron oxyhydroxide with oleic acid in high temperature ...solvents. Superconducting Quantum Interface Device (SQUID) measurements revealed that the iron oxide nanoparticles exhibit a superparamagnetic behavior at room temperature. In order to evaluate their potential applications as contrast agents in Nuclear Magnetic Resonance (NMR) imaging, we investigated using 1H NMR spectroscopy (at a magnetic field 4.7T) the changes in T1 and T2 relaxation times in the colloidal aqueous solution at various concentration of nanoparticles. The following transverse (r2) and longitudinal (r1) relaxivities were found: (r2=17.85mM−1s−1, r1=6.90mM−1s−1) and (r2=9.20mM−1s−1, r1=4.30mM−1s−1) for nanoparticle sizes of 18 and 6nm, respectively. These results confirm that the synthesized nanoparticles have both high r1 and r2 relaxivities and thus the capacity for positive or negative contrast enhancement. This effect increases with the nanoparticle size. We also developed a new recognition motif of a saccharide type (mannose coating) for targeting biological models (plants) at the tissue and cellular levels in order to track the flow of the water and saccharide (which are the main drivers of plant growth) in NMR imaging. Moreover, we demonstrated that this saccharide motif provides good biocompatibility and biodistribution in a physiological medium.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract Nondestructive studies of physiological processes in agronomic products require increasingly higher spatial and temporal resolutions. Nuclear Magnetic Resonance (NMR) imaging is a ...non-invasive technique providing physiological and morphological information on biological tissues. The aim of this study was to design a robust and accurate quantitative measurement method based on NMR imaging combined with contrast agent (CA) for mapping and quantifying water transport in growing cherry tomato fruits. A multiple flip-angle Spoiled Gradient Echo (SGE) imaging sequence was used to evaluate the intrinsic parameters maps M0 and T1 of the fruit tissues. Water transport and paths flow were monitored using Gd 3 + / Fe ( CN )6 3 − / D − mannitol nanoparticles as a tracer. This dynamic study was carried out using a compartmental modeling. The CA was preferentially accumulated in the surrounding tissues of columella and in the seed envelopes. The total quantities and the average volume flow of water estimated are: 198 mg , 1.76 mm3 / h for the columella and 326 mg , 2.91 mm3 / h for the seed envelopes. We demonstrate in this paper that the NMR imaging technique coupled with efficient and biocompatible CA in physiological medium has the potential to become a major tool in plant physiology research.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
By means of muon spin relaxation measurements we unraveled the temperature spin dynamics in monodisperse maghemite spherical nanoparticles with different surface to volume ratio, in two samples with ...a full core (diameter D ∼ 4 and D ∼ 5 nm) and one with a hollow core (external diameter D ∼ 7.4 nm). The behavior of the muon longitudinal relaxation rates as a function of temperature allowed us to identify two distinct spin dynamics. The first is well witnessed by the presence of a characteristic peak for all the samples around the so-called muon blocking temperature Tμ+B. A Bloembergen-Purcell-Pound (BPP)-like model reproduces the experimental data around the peak and at higher temperatures (20 < T < 100 K) by assuming the Néel reversal time of the magnetization as the dominating correlation time. An additional dynamic emerges in the samples with higher surface to volume ratio, namely, full 4 nm and hollow samples. This is witnessed by a shoulder of the main peak for T < 20 K at low longitudinal field (μ0H ≈ 15 mT), followed by an abrupt increase of the relaxation rate at T < 10 K, which is more evident for the hollow sample. These unusual anomalies of the longitudinal relaxation rate for T < Tμ+B are suggested to be due to the surface spins' dynamical behavior. Furthermore, for weak applied longitudinal magnetic field (μ0H ≈ 15 mT) and T < Tμ+B we observed damped coherent oscillations of the muon asymmetry, which are a signature of a quasistatic local field at the muon site as probed by muons implanted in the inner magnetic core of the nanoparticles. The muon spin relaxation technique turns out to be very successful to study the magnetic behavior of maghemite nanoparticles and to detect their unusual local spin dynamics in low magnetic field conditions.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Introduction.
One of the urgent tasks in the implementation of the federal project "Workforce for the Digital Economy", which is part of the national digital economy programme, the transition to the ...digital economy is the development of professional competencies for workers in various sectors in the field of end-to-end digital technology. The digital competencies are developed in response to the requirements of society, the state, and the labour market for the individual in the digital society.
Materials and Methods.
The analysis, generalization and systematization of scientific research, and personal experience of formation and development of digital competences allowed us to identify their universality and the end-to-end principle of mastering them, which allowed us to draw a conclusion about the feasibility and necessity of developing a pedagogical model for forming end-to-end digital competences of higher education students in non-core IT disciplines.
Results.
The research defines the concept of «transversal digital competences» (TDC) at the stage of digital transformation of higher education; presents components, criteria, indicators and indices of formation of transversal digital competences of students; presents a pedagogical model for shaping transversal digital competences of students of non-profile IT fields in a classical university in the process of additional professional education. The stages of formation of end-to-end digital competences of students are considered in detail, the purpose of pedagogical model, tasks, principles, factors and organizational and pedagogical conditions of formation are defined, the results of research are presented.
Discussion and Conclusions.
This pedagogical model was developed in the process of studying the conditions for the formation of digital competences and skills of using digital technologies in students at Kemerovo State University. Partially the results of this study were presented in the report «Basic principles of formation of end-to-end digital competences in students in the process of mastering additional professional programmes» at the II All-Russian scientific-practical conference with international participation «Digital humanities and educational technologies - DHTE 2021» (organizer - FSBEI VPO "Moscow State Psychological and Pedagogical University").