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Updated: May 11, 2026
09:25
Agarose-based Tissue Mimicking Optical Phantoms for Diffuse Reflectance Spectroscopy
Published on: August 22, 2018
Recipes to make organic phantoms for diffusive optical spectroscopy.
Giovanna Quarto1, Antonio Pifferi, Ilaria Bargigia
1Politecnico di Milano, Dipartimento di Fisica, Milano 20133, Italy. giovanna.quarto@mail.polimi.it
Applied Optics
|May 15, 2013
Summary
Researchers developed three recipes for creating tissue-equivalent phantoms using water and lipids. These phantoms, crucial for diffuse optical spectroscopy, demonstrated good homogeneity and reproducibility for various compositions.
Area of Science:
- Biomedical Optics
- Materials Science
- Optical Spectroscopy
Background:
- Accurate tissue-equivalent phantoms are essential for calibrating and validating diffuse optical spectroscopy (DOS) systems.
- Developing stable and homogeneous phantoms mimicking biological tissues' optical properties remains a challenge.
- Water and lipids are primary constituents influencing tissue optical properties.
Purpose of the Study:
- To present and evaluate three distinct recipes for fabricating tissue-equivalent phantoms composed of water and lipids.
- To investigate different emulsification methods, including nature (disperser only), agar, and Triton X-100.
- To characterize the optical properties and assess the homogeneity and reproducibility of the fabricated phantoms across various water-to-lipid ratios.
Main Methods:
- Fabrication of three types of phantoms: Nature (no emulsifier), Agar, and Triton X-100.
- Preparation of phantoms with varying mass fractions of water and lipids (30%–70%).
- Characterization using a broadband time-resolved diffuse optical spectroscopy system to determine optical properties (absorption and reduced scattering coefficients).
Main Results:
- Successful fabrication of homogeneous phantoms with low coefficients of variation (CV) for absorption (4.6%) and reduced scattering (1.5%).
- Demonstrated good reproducibility across phantom batches (CV of 8.3% for absorption, 12.4% for reduced scattering).
- Identified specific water/lipid ratios where emulsion stability or phantom lifetime was limited, though most formulations were successful.
Conclusions:
- The presented recipes offer reliable methods for creating stable, homogeneous, and reproducible water-lipid tissue-equivalent phantoms.
- These phantoms are suitable for applications in diffuse optical spectroscopy, aiding in system calibration and biological tissue optical property measurement.
- Further optimization may be needed for specific water/lipid ratios to ensure long-term phantom stability.
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