Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Novel on-line mid infrared detection strategies in capillary electrophoretic systems
Stockholm University, Faculty of Science, Department of Analytical Chemistry.
2005 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Infrared absorption spectra can provide analytically useful information on a large variety of compounds, ranging from small ions to large biological molecules. In fact, all analytes that possess a dipole moment that changes during vibration are infrared-active. The infrared (IR) spectrum can be subdivided into far-, mid- and near- regions. The focus of attention in this thesis is the mid-IR region, in which the fundamental vibrations of most organic compounds are located, thus providing scope for positive structural identification. However, while such near-ubiquitous signals can be very useful for monitoring simple molecules in simple systems, they can be increasingly disadvantageous as the number of analytes and/or the complexity of the sample matrix increases. Thus, hyphenation to a separation system prior to detection is desirable. Paper I appended to this thesis presents (for the first time) the on-line hyphenation between Fourier transform infrared spectroscopy, FTIR, and capillary zone electrophoresis, CZE. CZE is a highly efficient separation technique that separates ionic analytes with respect to their charge-to-size ratio. It is most commonly performed in aqueous buffers in fused silica capillaries. Since these capillaries absorb virtually all infrared light an IR-transparent flow cell had to be developed. In further studies (Paper II) the applicability of CZE is expanded to include neutral analytes by the addition of micelles to the buffer, and micellar electrokinetic chromatography, MEKC, was successfully hyphenated to FTIR for the first time. Paper III describes an application of the on-line CZE-FTIR technique in which non-UV-absorbing analytes in a complex matrix were separated, identified and quantified in one run.

Measuring aqueous solutions in the mid-IR region is not straightforward since water absorbs intensely in this region, sometimes completely, leaving no transmitted, detectable light. For this reason, quantum cascade lasers are interesting. These lasers represent a new type of mid-IR semiconducting lasers with high output power due to their ingenious design. The laser action lies within one conduction band (intersubband) and can be tailored to emit light in the entire mid-IR region using the same semiconducting material. To investigate their potential to increase the optical path length in aqueous solutions, these lasers were used with an aqueous flow system (Paper IV), and the experience gained in these experiments enabled hyphenation of such lasers to a CZE system (Paper V).

Place, publisher, year, edition, pages
Stockholm: Institutionen för analytisk kemi , 2005. , 60 p.
Keyword [en]
on-line hyphenation, mid infrared detection, capillary electrophoresis, FTIR, quantum cascade laser, aqueous samples
National Category
Analytical Chemistry
Identifiers
URN: urn:nbn:se:su:diva-629ISBN: 91-7155-102-6 (print)OAI: oai:DiVA.org:su-629DiVA: diva2:196295
Public defence
2005-09-22, Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 12 A, Stockholm, 13:30
Opponent
Supervisors
Available from: 2005-09-01 Created: 2005-09-01Bibliographically approved
List of papers
1. On-line Fourier transform infrared detection in capillary electrophoresis
Open this publication in new window or tab >>On-line Fourier transform infrared detection in capillary electrophoresis
Show others...
2002 In: Analytical Chemistry, ISSN 0003-2700, Vol. 74, no 15, 3843-3848 p.Article in journal (Refereed) Published
Identifiers
urn:nbn:se:su:diva-23994 (URN)
Note
Part of urn:nbn:se:su:diva-629Available from: 2005-09-01 Created: 2005-09-01Bibliographically approved
2. Micellar electrokinetic chromatography with on-line Fourier transform infrared detection
Open this publication in new window or tab >>Micellar electrokinetic chromatography with on-line Fourier transform infrared detection
2003 In: Electrophoresis, ISSN 0173-0835, Vol. 24, no 4, 687-692 p.Article in journal (Refereed) Published
Identifiers
urn:nbn:se:su:diva-23995 (URN)
Note
Part of urn:nbn:se:su:diva-629Available from: 2005-09-01 Created: 2005-09-01Bibliographically approved
3. Capillary electrophoretic separation of sugars in fruit juices using on-line mid infrared Fourier transform detection
Open this publication in new window or tab >>Capillary electrophoretic separation of sugars in fruit juices using on-line mid infrared Fourier transform detection
2005 In: Analyst, ISSN 0003-2654, Vol. 130, no 5, 772-778 p.Article in journal (Refereed) Published
Identifiers
urn:nbn:se:su:diva-23996 (URN)
Note
Part of urn:nbn:se:su:diva-629Available from: 2005-09-01 Created: 2005-09-01Bibliographically approved
4. Assessment of quantum cascade lasers as mid infrared light sources for measurements of aqueous solutions
Open this publication in new window or tab >>Assessment of quantum cascade lasers as mid infrared light sources for measurements of aqueous solutions
Show others...
2002 In: Vibrational Spectroscopy, ISSN 0924-2031, Vol. 29, no 1-2, 283-289 p.Article in journal (Refereed) Published
Identifiers
urn:nbn:se:su:diva-23997 (URN)
Note
Part of urn:nbn:se:su:diva-629Available from: 2005-09-01 Created: 2005-09-01Bibliographically approved
5. On-line hyphenation of quantum cascade laser and capillary electrophoresis
Open this publication in new window or tab >>On-line hyphenation of quantum cascade laser and capillary electrophoresis
2005 In: Journal of Chromatography A, ISSN 0021-9673, Vol. 1083, no 1-2, 199-204 p.Article in journal (Refereed) Published
Identifiers
urn:nbn:se:su:diva-23998 (URN)
Note
Part of urn:nbn:se:su:diva-629Available from: 2005-09-01 Created: 2005-09-01Bibliographically approved

Open Access in DiVA

fulltext(11446 kB)334 downloads
File information
File name FULLTEXT01.pdfFile size 11446 kBChecksum SHA-1
055ed57d59d0830f8aac98c148524bca59f6ce0a40ae2e46d464d061ba08a94212e37d52
Type fulltextMimetype application/pdf

By organisation
Department of Analytical Chemistry
Analytical Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 334 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 606 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf