Contrast by Quadrupole Enhanced Relaxation

Risultati finali

Test of uptake of particles into endothelial cells and into human PBMCs by microscopy and MRI. MRI will be done after cells have been incubated with different dilutions of the NPs and embedded in agarose. Contrast changes due to switching of B0 in phantoms and in cell cultures after cellular uptake will be studied and documented.

Quantum-mechanical model 1

An NQR-modeling approach which has been developed for solids will be extended towards different motional scenarios to account for rotational, translational and internal dynamics as well as exchange processes. Existing numerical tools will be used for initial simulations but the software will be continuously developed to account for the complex relaxation scenario. Optimisation is likely to be required as the computational complexity increases significantly for high spin (9/2) nuclei. Where necessary, the quantum-mechanical models will be combined with molecular dynamics simulations.

Scientific papers of reporting period 2

8 Scientific papers planned on theoretical modelling, synthesis of NQR-CR compounds and their characterisation as well as on toxicology and imaging results. Papers on the proof of concept.

Report on publications and events

Report on publications (journal and book articles, patents etc. as well as events such as workshops and mini-symposia on conferences.

Scientific papers of reporting period 1

3 Scientific papers planned on theoretical modelling, synthesis of NQR-CR compounds and their characterisation.

Cytotoxicity, uptake, inflammation

Cell cultures for MRI experiments will be prepared. Absence of biological contamination, sufficient cellular uptake and lack of adverse cellular effects will be shown with endothelial cells and blood cells. Contamination will be detected by subjecting the NPs to limulus amoebocyte lysate assay to test endotoxin levels Cytotoxicity and potential influence on the immune system will be studied and documented.

Tuned NPs characterised

After optimisation of the prototype particle system (size, chemistry and hydrophilicity the NQR properties will be tuned in order to fulfil the 3T conditions. Thus a fine tuning of the particle size, shape and slight chemical modifications may be required.

Modified MRI scanner characterised

"The existing clinical 3T scanner will be equipped with a coil insert for shifting B0 so as to change the NQR-CR (custom manufacturing by ""Resonance Research""). The RF coils used will be dedicated animal coils. Existing pulse sequences will be modified to control the coil insert and optimised for high SNR. The complete MRI setup will be validated and characterized with dedicated MRI phantoms. "

Extended quantum-mechanical model

Theoretical models and simulations for systems containing QN and paramagnetic ions, different kinds of QN, will be developed to explore the possibilities offered by multi-quantum effects. Although a comprehensive model is necessary for predicting in detail the contrast properties of the CA, we will also develop simplified, phenomenological ‗master rules‘ relating the shape of the NQR-CR peaks with structural and dynamical parameters. Due to their complexity the developed models will be thoroughly tested against experiments

Relaxometry data base tuned NPs

1H NMR Field Cycling studies for the final, fine-tuned compounds synthetised by WPs 3 and 4 will be carried out. The results will again be documented and stored in a database.

ZF-NQRS database

Zero field NQRS of promising prototype compounds from WP3 will be carried out. From the spectra the resonance frequencies and the facor eta will be deduced and the quantum-chemical computations in WP3 will be validated. The relative strength of the NQR peaks and the NQR relaxation times will be characterised to study the magnitude of the effects in different compounds. All data will be stored in a database.

Relaxometry database prototyping

1H NMR Field Cycling studies for selected prototype compounds synthesised by WPs 3 and 4 will be carried out. Preliminary measurements will be carried out in parallel to the theoretical simulations. The preliminary studies will be followed by detailed experimental investigations of specific systems selected on the basis of simulations to confirm or negate their potential as CA. All experimental results will be documented and stored in a database.

Dextran based NPs characterised

Immobilisation of the most promising candidates from WP3 (TUG) in terms of NQR frequencies onto dextranes differing in molecular weight and the degree of branching. The immobilisation will be performed by reacting the Bi compounds bearing a functional spacer group (e.g. carboxylic groups) with the polymers. For example, carbodiimide chemistry is a well-known procedure for coupling OH with COOH groups in a very efficient way, and several literature procedures are known. Purification (e.g. dialysis) of the polymers and nanoprecipitation under sonication conditions to create nano- and micro-particles with defined sizes according to the guidelines WP2 from UWM and UU. The sizes will be varied over two orders of magnitudes in order to explore the influence on relaxivity. (Task 4.2, UM, TUG, UWM) Characterisation of the NPs by state of the art techniques (Infrared spectroscopy, SWAXS, TEM, dynamic light scattering, zeta potential, ZF-NQRS, fast field cycling relaxometry).

NQR-CR polymers characterised

Immobilisation of the most promising candidates from WP3 in terms of NQR frequencies onto PEG differing in molecular weight and the degree of branching. The immobilisation will be performed by reacting the Bi compounds bearing a functional spacer group (e.g. carboxylic groups) with the polymers. For example, carbodiimide chemistry is a well-known procedure for coupling OH with COOH groups in a very efficient way, and several literature procedures are known. Purification (e.g. dialysis) of the polymers and nanoprecipitation under sonication conditions to create nano- and micro-particles with defined sizes according to the guidelines WP2 from UWM and UU. The sizes will be varied over two orders of magnitudes in order to explore the influence on relaxivity. Characterisation of the NPs by state of the art techniques (Infrared spectroscopy, SWAXS, TEM, dynamic light scattering, zeta potential, ZF-NQRS, fast field cycling relaxometry).

Data management plan

Detailed rules for data management, enabling data exchange by supplying appropriate channels and assurance of data security (server management).

Webpage with open access database

Design and implementation of a webpage for communicating general information and results, providing open access to data and for facilitating networking activities.

Pubblicazioni

An electronically tuned wideband probehead for NQR spectroscopy in the VHF range

Autori: Hermann Scharfetter
Pubblicato in: Journal of Magnetic Resonance, Numero 271, 2016, Pagina/e 90-98, ISSN 1090-7807
Editore: Academic Press
DOI: 10.1016/j.jmr.2016.08.008

A cryostatic, fast scanning, wideband NQR spectrometer for the VHF range

Autori: Hermann Scharfetter, Markus Bödenler, Dominik Narnhofer
Pubblicato in: Journal of Magnetic Resonance, Numero 286, 2018, Pagina/e 148-157, ISSN 1090-7807
Editore: Academic Press
DOI: 10.1016/j.jmr.2017.12.004

R 1 dispersion contrast at high field with fast field-cycling MRI

Autori: Markus Bödenler, Martina Basini, Maria Francesca Casula, Evrim Umut, Christian Gösweiner, Andreas Petrovic, Danuta Kruk, Hermann Scharfetter
Pubblicato in: Journal of Magnetic Resonance, Numero 290, 2018, Pagina/e 68-75, ISSN 1090-7807
Editore: Academic Press
DOI: 10.1016/j.jmr.2018.03.010

209 Bi quadrupole relaxation enhancement in solids as a step towards new contrast mechanisms in magnetic resonance imaging

Autori: D. Kruk, E. Umut, E. Masiewicz, C. Sampl, R. Fischer, S. Spirk, C. Goesweiner, H. Scharfetter
Pubblicato in: Physical Chemistry Chemical Physics, Numero 20/18, 2018, Pagina/e 12710-12718, ISSN 1463-9076
Editore: Royal Society of Chemistry
DOI: 10.1039/c8cp00993g

1 H relaxation and dynamics of triphenylbismuth in deuterated solvents

Autori: Danuta Kruk, Elzbieta Masiewicz, Evrim Umut, Hermann Scharfetter
Pubblicato in: Molecular Physics, 2018, Pagina/e 1-6, ISSN 0026-8976
Editore: Taylor & Francis
DOI: 10.1080/00268976.2018.1513175

Tuning Nuclear Quadrupole Resonance: A Novel Approach for the Design of Frequency-Selective MRI Contrast Agents

Autori: Christian Gösweiner, Perttu Lantto, Roland Fischer, Carina Sampl, Evrim Umut, Per-Olof Westlund, Danuta Kruk, Markus Bödenler, Stefan Spirk, Andreas Petrovič, Hermann Scharfetter
Pubblicato in: Physical Review X, Numero 8/2, 2018, ISSN 2160-3308
Editore: American Physical Society
DOI: 10.1103/PhysRevX.8.021076

Model – free approach to quadrupole spin relaxation in solid 209 Bi-aryl compounds

Autori: Danuta Kruk, Christian Goesweiner, Elzbieta Masiewicz, Evrim Umut, Carina Sampl, Hermann Scharfetter
Pubblicato in: Physical Chemistry Chemical Physics, Numero 20/36, 2018, Pagina/e 23414-23423, ISSN 1463-9076
Editore: Royal Society of Chemistry
DOI: 10.1039/C8CP03848A

1 H spin–lattice relaxation in water solution of 209 Bi counterparts of Gd 3+ contrast agents

Autori: Danuta Kruk, Evrim Umut, Elzbieta Masiewicz, Petr Hermann, Hermann Scharfetter
Pubblicato in: Molecular Physics, 2018, Pagina/e 1-8, ISSN 0026-8976
Editore: Taylor & Francis
DOI: 10.1080/00268976.2018.1517907

Predicting quadrupole relaxation enhancement peaks in proton R 1 -NMRD profiles in solid Bi-aryl compounds from NQR parameters

Autori: Christian Gösweiner, Danuta Kruk, Evrim Umut, Elzbieta Masiewicz, Markus Bödenler, Hermann Scharfetter
Pubblicato in: Molecular Physics, 2018, Pagina/e 1-11, ISSN 0026-8976
Editore: Taylor & Francis
DOI: 10.1080/00268976.2018.1519201

Aspects of structural order in 209 Bi-containing particles for potential MRI contrast agents based on quadrupole enhanced relaxation

Autori: Hermann Scharfetter, Christian Gösweiner, Paul Josef Krassnig, Carina Sampl, Martin Thonhofer, Roland Fischer, Stefan Spirk, Rupert Kargl, Karin Stana-Kleinschek, Evrim Umut, Danuta Kruk
Pubblicato in: Molecular Physics, 2018, Pagina/e 1-9, ISSN 0026-8976
Editore: Taylor & Francis
DOI: 10.1080/00268976.2018.1511869

Comparison of fast field-cycling magnetic resonance imaging methods and future perspectives

Autori: Markus Bödenler, Ludovic de Rochefort, P. James Ross, Nicolas Chanet, Geneviève Guillot, Gareth R. Davies, Christian Gösweiner, Hermann Scharfetter, David J. Lurie, Lionel M. Broche
Pubblicato in: Molecular Physics, Numero 117/7-8, 2018, Pagina/e 832-848, ISSN 0026-8976
Editore: Taylor & Francis
DOI: 10.1080/00268976.2018.1557349

Quadrupole relaxation enhancement and polarisation transfer in DMSO solution of [Bi(NO 3 ) 3 (H 2 O) 3 ]*18-crown-6 in solid state

Autori: Danuta Kruk, Elzbieta Masiewicz, Evrim Umut, Martin Schlögl, Roland Fischer, Hermann Scharfetter
Pubblicato in: Molecular Physics, Numero 117/7-8, 2018, Pagina/e 944-951, ISSN 0026-8976
Editore: Taylor & Francis
DOI: 10.1080/00268976.2018.1552798

Effect of different surface active polysaccharide derivatives on the formation of ethyl cellulose particles by the emulsion-solvent evaporation method

Autori: Mojca Božič, Thomas Elschner, Doris Tkaučič, Matej Bračič, Silvo Hribernik, Karin Stana Kleinschek, Rupert Kargl
Pubblicato in: Cellulose, Numero 25/12, 2018, Pagina/e 6901-6922, ISSN 0969-0239
Editore: Blackie Academic & Professional
DOI: 10.1007/s10570-018-2062-2

Risultati finali

Pubblicazioni

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