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Virtual Journal for Biomedical Optics

Virtual Journal for Biomedical Optics


  • Editor: Gregory W. Faris
  • Vol. 4, Iss. 9 — Sep. 4, 2009

Terahertz Spectroscopic Differentiation of Microstructures in Protein Gels

Gretel M. Png, Robert J. Falconer, Bernd M. Fischer, Hidayatul A. Zakaria, Samuel P. Mickan, Anton P.J. Middelberg, and Derek Abbott  »View Author Affiliations

Optics Express, Vol. 17, Issue 15, pp. 13102-13115 (2009)

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We demonstrate that terahertz (THz) spectroscopy can be used to differentiate soft protein microstructures. Differentiation of soft microstructures in gels has to date been performed using optical imaging techniques (e.g. electron microscope) and Fourier Transform Infra-Red (FTIR) spectroscopy for the mid-IR range, but a differentiation tool for the THz frequency range is lacking. Particulate and fine-stranded (fibrillar) soft protein microstructures are of interest, particularly to medical researchers, because they form from naturally occurring proteins that are thought to be involved in several human diseases, such as Alzheimer’s disease. In this study, globular β-lactoglobulin structures with diameters of 2 µm, and fibrillar structures with diameters less than 0.03 µm are observed between 0.8 and 1.5 THz. Results show that the globular structures have a decline in THz transmission when compared to the fibrillar ones. The cause of this decline is possibly due to Rayleigh scattering from the globular microstructures.

© 2009 Optical Society of America

OCIS Codes
(170.0170) Medical optics and biotechnology : Medical optics and biotechnology
(300.6495) Spectroscopy : Spectroscopy, teraherz

ToC Category:

Original Manuscript: May 18, 2009
Revised Manuscript: July 1, 2009
Manuscript Accepted: July 1, 2009
Published: July 16, 2009

Virtual Issues
Vol. 4, Iss. 9 Virtual Journal for Biomedical Optics

Gretel M. Png, Robert J. Falconer, Bernd M. Fischer, Hidayatul A. Zakaria, Samuel P. Mickan, Anton P. J. Middelberg, and Derek Abbott, "Terahertz Spectroscopic Differentiation of Microstructures in Protein Gels," Opt. Express 17, 13102-13115 (2009)

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