Thesis-1992-Wang.pdf (2.25 MB)
Retention Studies In HPLC
thesis
posted on 2012-10-09, 14:25 authored by Yuan WangThe effect of increasing temperature on retention time, efficiency and peak
symmetry on a PS-DVB column was investigated using two sets of homologous
compounds, phenylalkanols (benzyl alcohol to 5-phenylpentanol) and alkyl aryl
ketones (benzaldehyde to heptanophenone) as standard compounds. It was found
that efficiency and peak symmetry can be improved by an increase of temperature
in both RP-HPLC and NP-HPLC In NP-HPLC, the use of a low level of polar organic
modifier can reduce retention times and give improved peak shapes and column
efficiencies. A different elution order was obtained in RP-HPLC compared with
NP-HPLC
The study was extended to retention prediction in RP-HPLC Retention indices
can be calculated from the molecular structure of a compound as the sum of the
parent index, substituent indices, and interaction indices. In this study the
substituent contributions have been determined for 7 aromatic functional groups
and 8 aliphatic functional groups over a range of methanol, acetonitrile and THF
buffer eluents based on the alkyl aryl ketone retention index scale. The effect of
intramolecular hydrogen-bonding in THF has been studied. A general prediction
model was used for the retention prediction of disubstituted compounds. It was
found -that the use of the Hammett constant (0") had its limitations and was not
suitable if THF was the eluent.
History
School
- Science
Department
- Chemistry
Publisher
© Yuan WangPublication date
1992Notes
A Doctoral Thesis submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.Language
- en