Title:
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Spectroscopic studies of pharmaceutical and biological materials
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Chapter 1: Introduction
An introduction into the studies of the pharmaceutical materials and FTiR of biological materials are
presented.
Chapter 2: Quantification of amorphous lactose using HID exchange coupled
with Raman, FTIR and ss-NMR spectroscopies
Three analytical techniques coupled with HID exchange are used for quantification of the
amorphous content in blends of amorphous and crystalline lactose. Firstly, Raman spectroscopy was
used to quantify mixtures pre- and post-deuteration. Prior to deuteration, a known method was
utilised using peak height ratios and this showed linearity across the entire percentage amorphous
content range with a detection limit of 2.2 %. Post-deuteration, a similar linear trend was observed
with the limit of detection found to be 1.5 %. The second technique presented is FTIR where a
similar approach was adopted. Before deuteration, bands indicative of either the amorphous or
crystalline phase were selected and then used to create a calibration with a limit of detection of
1.47 %. Following deuteration of the blends, the v(O-D) band was integrated and used to construct a
further calibration with detection limit equal to 0.7%. Finally 2H solid-state NMR was used and
following initial calibration experiments, blends of amorphous and crystalline lactose were collected
and the calibration plot had limit of detection of 0.4 %.
To extend the data analysis, Principal Component Analysis, a multivariate technique, was employed
to the post deuteration FTIR dataset. This gave a new calibration with the detection limit 0.44 %.
Chapter 3: Quantification of amorphous cimetidine using HID exchange
coupled with Raman, FTIR and ss-NMR spectroscopies
A brief recap of previous work complete in the group is presented here, using FT-Raman for the
quantification of amorphous cimetidine. The FT-Raman work is then repeated using a dispersive
Raman system with a different excitation wavelength. The 785 nm system gave improved limits of
detection for both undeuterated cimetidine and deuterated cimetidine compared with the FTRaman
work, with the limits of detection 1.95 % and 4.1 % respectively. Cimetidine was further
investigated using FTIR. It was found that quantification of amorphous cimetidine could not be
performed as incomplete deuteration was observed. A solution casting method was developed,
which did allow for the complete deuteration of amorphous cimetidine, however, this was not
suitable for quantification purposes. 2H solid-state NMR experiments were performed on blends of
deuterated amorphous and crystalline cimetidine and following data processing, a calibration plot
was constructed. The limit of detection was 1.6 %.
Principal component analysis was applied to the deuterated Raman spectra, this gave an
improvement in the limit of detection equal to 1.4 %, bring the detection limit down to 2.7 %
amorphous content.
Chapter 4: Investigation using FTIR for the prognosis of Breast Cancer using
FTIR instrumentation with 25 JIm spatial resolution
FTIR images were collected from 8 breast cancer tissue sections (2 Grade 1, 3 Grade 2 and 3 Grade3).
Each of the FTIR datasets was subjected to Principal Component Analysis for explore the patterns in
the data. Two methods have been presented to construct false colour images, PCA- Fuzzy c-means
clustering and Multivariate Curve Resolution and the ability of each multivariate technique to discriminate different tissue types is discussed. Spectra were extracted from regions of tumour and
normal cells and then analysed to investigate the possibility of differentiating between the two cell
types. It was found that it was possible to discriminate between the two. Finally spectra were
extracted from the tumour regions of the different tissues in order to study whether grading of the
breast cancer was possible using FTIR imaging. However, no clear relationship was observed
between the different grades .
. Chapter 5: Investigation using FTIR for the prognosis of Breast Cancer with
5.5 ~m pixel size
A similar approach to Chapter 5 was adopted but imaging the tissue sections with a focal plane array
detector with pixel size 5.5 ~m. The increased spatial resolution allowed for false colour images with
increased similarity to the H&E to be constructed . Finally FTIR imaging was used to successfully
grade the breast cancer tissues in a non-subjective way, using PCA. .
Chapter 6: Experimental
The methods used to perform the experiments presented in this Thesis are outlined, as well as an
introduction to the chemometric techniques that have been utilised.
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