Study of fragmentation ketones and identification fatty acids with high resolution mass spectrometry

Postgraduate Thesis uoadl:1318883 637 Read counter

Unit:
Κατεύθυνση Οργανική Χημεία
Library of the School of Science
Deposit date:
2016-06-07
Year:
2016
Author:
Βλάσση-Κλεπετσάνη Ζωή
Supervisors info:
Γεώργιος Κόκοτος Καθηγητής
Original Title:
Μελέτης της θραυσματοποίησης κετονών και του προσδιορισμού λιπαρών οξέων με φασματομετρία μάζας υψηλής διακριτικής ικανότητας
Languages:
Greek
Translated title:
Study of fragmentation ketones and identification fatty acids with high resolution mass spectrometry
Summary:
In this study, the synthesis of four fluoroketones was carried out aiming
tostudy usingtheir fragmentation high resolution mass spectrometry. The study
of fragmentation pathways of specific class of compounds is of high interest,
because the knowledge of the fragments can both streamline the identification
process and facilitate the identification of unknown compounds in non-targeted
analysis.
In particular, the objective was the study of fragmentation ofcommercially
available cyclic ketones and fluoroketones, both in positive and negative
ionization, using electrospray ionization technique (ESI) and additionally the
fragmentation study of polyfluoroketones, some of which were synthesized.
In the mass spectra of commercially available fluoroketones, primarily the
Na+adduct and the protonated ions were observed, however in the negative
ionization the deprotonated ions were not observed. In the mass spectra of
synthetic fluoroketones mainly the deprotonated ions were observed, whilst in
the positive ionization neither the protonated ions nor the Na+adduct were
observed.
The aim was also to study ten free fatty acids and short-chain acids in human
serum of healthy individuals. Particularly the identification of butyric acid,
valeric acid, caprylic acid, lauric acid, myristic acid, arachidonic acid,
linoleic acid, oleic acid, sapienic acid and linolenic acid. Study of sample
preparation is a key step for the successful identification. For this reason,
we studied three systems for liquid-liquid extraction with: CHCl3 / MeOH, HCl /
MeOH /iIsooctane, and MTBE / HCl / MeOH. The best results were obtained using
CHCl3 / MeOH. Then we examined a small number of sample of healthy people
(three men and three women, in the 33 to 46 age group) in order to study the
levels of these fatty acids.
Keywords:
Fluoroketones, Fragmentation, Positive Ionization, Negative Ionization, Free Fatty Acids
Index:
Yes
Number of index pages:
1-6
Contains images:
Yes
Number of references:
55
Number of pages:
147
File:
File access is restricted.

document.pdf
4 MB
File access is restricted.