LC - ¹³C NMR utilizing dynamic nuclear polarization (DNP) for signal enhancement

Simple item page
dc.contributor.authorStevenson, Steven A.en
dc.contributor.committeechairDorn, Harry C.en
dc.contributor.committeememberAnderson, Mark R.en
dc.contributor.committeememberTaylor, Larry T.en
dc.contributor.departmentAnalytical Chemistryen
dc.date.accessioned2014-03-14T21:46:12Zen
dc.date.adate2009-09-19en
dc.date.available2014-03-14T21:46:12Zen
dc.date.issued1992-06-05en
dc.date.rdate2009-09-19en
dc.date.sdate2009-09-19en
dc.description.abstractThe primary difficulty for successful LC - ¹³C NMR (whether ¹H or ¹³C) is overcoming the relatively low sensitivity of NHR as a chromatographic detector. For the ¹H nuclide this is much less of a problem; the sensitivity ;s approximately 6000 times more sensitive than that of ¹³C nuclei. For this reason, much of the literature focuses on LC - ¹H NMR. To ever successfully realize LC - ¹³C NMR, it is mandatory that an augmentation of ¹³C signal intensity must be effectuated to overcome this sensitivity deficit (~ three orders of magnitude). To satisfy this requirement, our laboratory has utilized dynamic nuclear polarization (DNP) to ameliorate these otherwise weak or non-existent signals. For favorable molecules, sensitivity recoveries of up to two orders of magnitude have been developed. This improvement (relative to 'H) narrows the sensitivity gap between 'H and ¹³C NMR detection of chromatographically separated analytes. Despite the fact that relatively large injection volumes were required in most LC experiments, the wealth of structural information inherent to ¹³C NMR justifies any attempt to successfully couple nuclear magnetic resonance to liquid chromatography. In addition, DNP was utilized in a series of SLIT and LLIT experiments where a test mixture was recycled through a NMR spectrometer. Results indicate that ¹³C spectra were obtained with a significantly higher signal-to-noise ratio in a shorter amount of analysis time relative to experiments where DNP was not employed for signal enhancement.en
dc.description.degreeMaster of Scienceen
dc.format.extentxv, 147 leavesen
dc.format.mediumBTDen
dc.format.mimetypeapplication/pdfen
dc.identifier.otheretd-09192009-040407en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-09192009-040407/en
dc.identifier.urihttp://hdl.handle.net/10919/44860en
dc.language.isoenen
dc.publisherVirginia Techen
dc.relation.haspartLD5655.V855_1992.S748.pdfen
dc.relation.isformatofOCLC# 27690884en
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subject.lccLD5655.V855 1992.S748en
dc.subject.lcshLiquid chromatographyen
dc.subject.lcshNuclear magnetic resonanceen
dc.subject.lcshPolarization (Nuclear physics)en
dc.titleLC - ¹³C NMR utilizing dynamic nuclear polarization (DNP) for signal enhancementen
dc.typeThesisen
dc.type.dcmitypeTexten
thesis.degree.disciplineAnalytical Chemistryen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
LD5655.V855_1992.S748.pdf
Size:
3.39 MB
Format:
Adobe Portable Document Format
Download

Collections

Masters Theses