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Time-Resolved Spectroscopy for Pharmaceutical Applications

Abrahamsson, Christoffer LU (2005) In LRAP-348
Abstract
The work presented in this thesis aims at improving spectroscopic techniques for analysis of pharmaceutical solids. This improvement is achieved by the combining and development of instrumentations and data evaluation tools from two research fields: the fields of near infrared spectroscopy and biomedical optics.



The thesis include the construction and evaluation of different variable selection techniques. Variable selection is an important tool used to improve the evaluation of spectroscopic data. Variable selection was applied to near infrared data from pharmaceutical tablets and mid-infrared data from atmospheric gases.



A novel instrumentation, using a photonic crystal fibre for light generation and... (More)
The work presented in this thesis aims at improving spectroscopic techniques for analysis of pharmaceutical solids. This improvement is achieved by the combining and development of instrumentations and data evaluation tools from two research fields: the fields of near infrared spectroscopy and biomedical optics.



The thesis include the construction and evaluation of different variable selection techniques. Variable selection is an important tool used to improve the evaluation of spectroscopic data. Variable selection was applied to near infrared data from pharmaceutical tablets and mid-infrared data from atmospheric gases.



A novel instrumentation, using a photonic crystal fibre for light generation and a streak camera for detection, was developed, tested and used for time-resolved measurements. The system covers a wavelength range from 500 to 1200 nm and the time-resolution was measured to be 30 ps. The system proved to be very versatile and was used both for reflectance and transmission measurements.



New evaluation schemes for time-resolved data were developed. A new algorithm, based on diffusion theory was evaluated using time-resolved data required on apples. The same data was used to study the performance of a data evaluation scheme based on diffusion theory combined with least square support vector machines. Both tested evaluation schemes showed results comparable with results computed by the conventional evaluation scheme based on diffusion theory.



Time-resolved measurements were conducted on pharmaceutical solids. Quantitative analysis of intact tablets using time-resolved data was superior to analysis made using conventional near infrared data, especially when the difference in physical properties between the measured samples were large. An analysis method combining time-resolved spectroscopy and conventional near infrared spectroscopy was also developed. The scheme allows evaluation over a larger wavelength range than the one covered by the time-resolved system. The maximum range is only limited to the range covered by the near infrared spectroscopic instrument. The work also takes the first step toward the construction of a bench-top system, showing that the data from a simplified time-resolved system would still give valuable results. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Professor Griffiths, Peter, Department of Chemistry, University of Idaho, USA
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Elektromagnetism, optik, Near-infrared spectroscopy, Time-resolved spectroscopy, Pharmaceutical analysis, Multivariate data analysis, Electromagnetism, Light transport in turbid media, Photon migration, akustik, acoustics, optics
in
LRAP-348
pages
166 pages
publisher
Atomic Physics, Department of Physics, Lund University
defense location
Room B, Department of Physics, Professorsg 1, Lund Institute of Technology
defense date
2005-10-31 10:15
ISSN
0281-2762
ISBN
91-628-6613-3
language
English
LU publication?
yes
id
68cda59d-d7b7-44c8-b571-0cbce0e17d61 (old id 545495)
date added to LUP
2007-09-28 09:09:47
date last changed
2016-09-19 08:44:56
@phdthesis{68cda59d-d7b7-44c8-b571-0cbce0e17d61,
  abstract     = {The work presented in this thesis aims at improving spectroscopic techniques for analysis of pharmaceutical solids. This improvement is achieved by the combining and development of instrumentations and data evaluation tools from two research fields: the fields of near infrared spectroscopy and biomedical optics.<br/><br>
<br/><br>
The thesis include the construction and evaluation of different variable selection techniques. Variable selection is an important tool used to improve the evaluation of spectroscopic data. Variable selection was applied to near infrared data from pharmaceutical tablets and mid-infrared data from atmospheric gases.<br/><br>
<br/><br>
A novel instrumentation, using a photonic crystal fibre for light generation and a streak camera for detection, was developed, tested and used for time-resolved measurements. The system covers a wavelength range from 500 to 1200 nm and the time-resolution was measured to be 30 ps. The system proved to be very versatile and was used both for reflectance and transmission measurements.<br/><br>
<br/><br>
New evaluation schemes for time-resolved data were developed. A new algorithm, based on diffusion theory was evaluated using time-resolved data required on apples. The same data was used to study the performance of a data evaluation scheme based on diffusion theory combined with least square support vector machines. Both tested evaluation schemes showed results comparable with results computed by the conventional evaluation scheme based on diffusion theory.<br/><br>
<br/><br>
Time-resolved measurements were conducted on pharmaceutical solids. Quantitative analysis of intact tablets using time-resolved data was superior to analysis made using conventional near infrared data, especially when the difference in physical properties between the measured samples were large. An analysis method combining time-resolved spectroscopy and conventional near infrared spectroscopy was also developed. The scheme allows evaluation over a larger wavelength range than the one covered by the time-resolved system. The maximum range is only limited to the range covered by the near infrared spectroscopic instrument. The work also takes the first step toward the construction of a bench-top system, showing that the data from a simplified time-resolved system would still give valuable results.},
  author       = {Abrahamsson, Christoffer},
  isbn         = {91-628-6613-3},
  issn         = {0281-2762},
  keyword      = {Elektromagnetism,optik,Near-infrared spectroscopy,Time-resolved spectroscopy,Pharmaceutical analysis,Multivariate data analysis,Electromagnetism,Light transport in turbid media,Photon migration,akustik,acoustics,optics},
  language     = {eng},
  pages        = {166},
  publisher    = {Atomic Physics, Department of Physics, Lund University},
  school       = {Lund University},
  series       = {LRAP-348},
  title        = {Time-Resolved Spectroscopy for Pharmaceutical Applications},
  year         = {2005},
}