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NMR Studies of Gel-Emulsions; Diffusometry and Applications of Novel Field Gradient Techniques

Malmborg, Carin LU (2007)
Abstract (Swedish)
Popular Abstract in Swedish

Avsikten med detta arbetet har varit att utveckla kärnmagnetisk resonans, NMR, tekniken, applicerat på gel-emulsioner. Gel-emulsioner är viktiga i många tekniska formuleringar så som i livsmedel, i kosmetika, i läkemedelsformuleringar och i sprängmedel för att nämna några applikationer. Vi har arbetat med en teknik som kallas NMR diffusometri, som utvecklats av Stejskal, Tanner och Callaghan. Vi har preparerat gel-emulsionens vattenfas med enkla molekyler som agerar som modellsubstanser för läkemedel, likaväl som riktiga läkemedel som lidokain, för att klargöra teknikens användbarhet.



I porösa material mäter NMR diffusometri den medelkvadratiska förflyttningen under en viss... (More)
Popular Abstract in Swedish

Avsikten med detta arbetet har varit att utveckla kärnmagnetisk resonans, NMR, tekniken, applicerat på gel-emulsioner. Gel-emulsioner är viktiga i många tekniska formuleringar så som i livsmedel, i kosmetika, i läkemedelsformuleringar och i sprängmedel för att nämna några applikationer. Vi har arbetat med en teknik som kallas NMR diffusometri, som utvecklats av Stejskal, Tanner och Callaghan. Vi har preparerat gel-emulsionens vattenfas med enkla molekyler som agerar som modellsubstanser för läkemedel, likaväl som riktiga läkemedel som lidokain, för att klargöra teknikens användbarhet.



I porösa material mäter NMR diffusometri den medelkvadratiska förflyttningen under en viss tid, som ger information om materialets cellstorlek och hindrande effekter från cellmembran. Den här tekniken kan också mäta cellstorleksförändringar med avseende på tiden. För att mäta diffusionen på kort tidsskala, till exempel diffusionen i en emulsionsdroppe, har vi använt en teknik med modulerade fältgradient spin-eko puls tåg. Vi har också använt en teknik kallad kemiskt shifts avbildning av molekulär transport i gel-emulsioner. Med den här tekniken kan vi avbilda den spatiala fördelninen av molekyler som en function av tid. I utvärderingen av data från dessa tekniker används ofta en approximation, kort gradient puls approximationen, med kaliteten från den utkomman datan är diskuterbar, vi har utvärderat detta problemet.



NMR diffusometri tekniken mäter diffusion från 100 µs upp till några sekunder, och den medelkvadratiska förflyttningen i µm skala, och har många fördelar; den är snabb, kräver ingen märkning av isotoper eller tillsats av några störande ämnen, endast en liten provvolym behövs, och det är en icke-förstörande teknik (provet kan utvärderas flera gånger). (Less)
Abstract
The aim of these studies has been to investigate what information that can be obtained on gel-emulsions with nuclear magnetic resonance, NMR, as the investigating tool. The gel-emulsions are important in many technical applications such as in food products, in cosmetic and pharmaceutical formulations, and in emulsion explosives, just to name a few applications. We have worked with the NMR diffusometry technique as developed by Stejskal, Tanner and Callaghan, and have loaded the gel-emulsion water phase with simple molecules acting as model drugs, as well as ordinary drugs such as lidocaine to clarify the usefulness of this technique.



In porous materials the NMR diffusometry technique measures the mean square... (More)
The aim of these studies has been to investigate what information that can be obtained on gel-emulsions with nuclear magnetic resonance, NMR, as the investigating tool. The gel-emulsions are important in many technical applications such as in food products, in cosmetic and pharmaceutical formulations, and in emulsion explosives, just to name a few applications. We have worked with the NMR diffusometry technique as developed by Stejskal, Tanner and Callaghan, and have loaded the gel-emulsion water phase with simple molecules acting as model drugs, as well as ordinary drugs such as lidocaine to clarify the usefulness of this technique.



In porous materials the NMR diffusometry technique measures the mean square displacement, which gives information on structure and obstruction effects. This technique can also measure the emulsion break down process. To measure the diffusion on very short time scales, as in small emulsion droplets, we have used a novel technique with modulated field gradient spin echo pulse trains. We have also applied the chemical shift imaging technique of molecular transport in gel-emulsions. With this technique we can monitor the spatial distribution of solutes as a function of time. In the interpretation of data from the application of these techniques one often uses the short gradient pulse limit approximation, but the quality of the information is a matter of some uncertainty. We have provided some insight on this problem.



The NMR diffusometry technique measures diffusion in a time-window from a few 100 µs up to several seconds, and the root mean square displacement in the µm range, and have many advantages as; it is rapid, does not require any isotopic labelling or addition of disturbing probes, only small amounts of sample is needed, and it is a non-destructive method (the same sample can be repeatedly studied). (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Prof. Dr. Schönhoff, Monika, Institut für Physikalische Chemie, Universität Münster, Germany.
organization
publishing date
type
Thesis
publication status
published
subject
keywords
modulated gradients, imaging, Physical chemistry, Fysikalisk kemi, NMR, emulsion, diffusion
pages
49 pages
publisher
Physical Chemistry 1, Lund University
defense location
room A, Center for chemistry and chemical engineering, Lund University, Lund, Sweden
defense date
2007-06-15 10:15
ISBN
978-91-7422-151-0
language
English
LU publication?
yes
id
c6dab31f-8c27-448d-869f-14a3ba67641d (old id 548769)
date added to LUP
2007-10-09 12:43:12
date last changed
2016-09-19 08:45:08
@misc{c6dab31f-8c27-448d-869f-14a3ba67641d,
  abstract     = {The aim of these studies has been to investigate what information that can be obtained on gel-emulsions with nuclear magnetic resonance, NMR, as the investigating tool. The gel-emulsions are important in many technical applications such as in food products, in cosmetic and pharmaceutical formulations, and in emulsion explosives, just to name a few applications. We have worked with the NMR diffusometry technique as developed by Stejskal, Tanner and Callaghan, and have loaded the gel-emulsion water phase with simple molecules acting as model drugs, as well as ordinary drugs such as lidocaine to clarify the usefulness of this technique.<br/><br>
<br/><br>
In porous materials the NMR diffusometry technique measures the mean square displacement, which gives information on structure and obstruction effects. This technique can also measure the emulsion break down process. To measure the diffusion on very short time scales, as in small emulsion droplets, we have used a novel technique with modulated field gradient spin echo pulse trains. We have also applied the chemical shift imaging technique of molecular transport in gel-emulsions. With this technique we can monitor the spatial distribution of solutes as a function of time. In the interpretation of data from the application of these techniques one often uses the short gradient pulse limit approximation, but the quality of the information is a matter of some uncertainty. We have provided some insight on this problem.<br/><br>
<br/><br>
The NMR diffusometry technique measures diffusion in a time-window from a few 100 µs up to several seconds, and the root mean square displacement in the µm range, and have many advantages as; it is rapid, does not require any isotopic labelling or addition of disturbing probes, only small amounts of sample is needed, and it is a non-destructive method (the same sample can be repeatedly studied).},
  author       = {Malmborg, Carin},
  isbn         = {978-91-7422-151-0},
  keyword      = {modulated gradients,imaging,Physical chemistry,Fysikalisk kemi,NMR,emulsion,diffusion},
  language     = {eng},
  pages        = {49},
  publisher    = {ARRAY(0x8dd2968)},
  title        = {NMR Studies of Gel-Emulsions; Diffusometry and Applications of Novel Field Gradient Techniques},
  year         = {2007},
}