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Measurement of Particle Size Distribution in Turbid Solutions by Dynamic Light Scattering Microscopy
Published on: January 9, 2017
Characterizing liquid turbid media by frequency-domain photon-migration spectroscopy.
Biju Cletus1, Rainer Künnemeyer, Paul Martinsen
1The University of Waikato, Hillcrest Road, Hamilton, Waikato 3210, New Zealand. biju@waikato.ac.nz
Journal of Biomedical Optics
|May 2, 2009
Summary
A new tunable instrument accurately measures optical properties of turbid media like Intralipid. This frequency-domain system precisely quantifies absorption and scattering coefficients for liquid phantoms.
Area of Science:
- Biomedical Optics
- Photonics
- Optical Measurement
Background:
- Characterizing turbid media is crucial for applications like medical imaging and diagnostics.
- Accurate optical property measurements (absorption and scattering) are essential for developing new technologies.
Purpose of the Study:
- To develop and validate a wavelength-tunable, frequency-domain instrument for characterizing liquid turbid media.
- To measure the absorption and reduced scattering coefficients of Intralipid solutions across a specific wavelength range.
Main Methods:
- Utilized a tunable titanium-sapphire laser modulated by an acousto-optic modulator.
- Measured optical properties of Intralipid(R) 20% (0.94-4.00% concentrations) from 710-850 nm.
- Calculated absorption and reduced scattering coefficients with standard errors of 1% and 2.5%.
Main Results:
- Absorption coefficient extrapolation to 0% Intralipid closely matched pure water values (overestimation <10%).
- Reduced scattering coefficient measurements at 750 nm were consistent with published data within experimental error.
- Reduced scattering coefficient was found to underestimate Mie theory predictions by approximately 9%.
Conclusions:
- The developed instrument provides accurate characterization of optical properties for turbid media.
- The findings validate the instrument's performance and provide insights into the optical properties of Intralipid solutions.
- This technology can advance research and development in areas requiring precise optical property measurements of biological tissues and phantoms.
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