Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497261
Title: The application of nuclear quadrupole resonance to pharmaceutical analysis
Author: Tate, Elizabeth Alice Kate
Awarding Body: King's College London
Current Institution: King's College London (University of London)
Date of Award: 2007
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Abstract:
Research was conducted using nuclear quadrupole resonance (NQR) to investigate its potential application to pharmaceutical analysis. 14-nitrogen and 35-chlorine quadrupole resonance frequencies between 1 and 37 MHz have been established and characterised for a number of materials of pharmaceutical and chemical interest with a view to applying the technique of NQR to pharmaceutical analysis, possibly on an industrial scale. Background information and the theory of nuclear quadrupole resonance are discussed, together with the experimental hardware used, personal instrumental modifications made, pulse sequences and data processing methods. The characterisation of materials by other methods currently used in analysis, such as infrared and X-ray spectroscopy, thermogravimetric analysis and differential scanning calorimetry, are described and the limits of such techniques compared to those of NQR. Furosemide, heroin hydrochloride monohydrate, heroin, triazole, histidine, chloroquine diphosphate, dipicolinic acid and 4-methylimidazole have all been studied and characterisedto varying degrees with their NQR frequencies, line widths, temperature coefficients, and relaxation rates having been found experimentally. The ability to distinguish between polymorphs has been shown in furosemide - an important consideration in the manufacture of medicines. Quantification using both 14-N and 35-Cl signalsh as been demonstrated with mass of material being predicted to within 5% in triazole and furosemidc, using free induction decay and pulse-spin locking echo signals respectively. Quantification of two materials within the same container has been combined with signal processing techniques in the study of histidine and 4- methylimidazole. The ability to predict quadrupolar parameters by theoretical calculation has been shown to be feasible in the case of 14-N nuclei within heroin hydrochloride monohydratc by modelling. Finally, future perspectives are discussed and the possibilities and potential of industrial application considered.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.497261  DOI: Not available
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