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Iron-oxide nanoparticles as a contrast agent in thermoacoustic tomography

Jin, Xing and Keho, Aaron and Meissner, Kenith and Wang, Lihong V. (2007) Iron-oxide nanoparticles as a contrast agent in thermoacoustic tomography. In: Photons Plus Ultrasound: Imaging and Sensing 2007: The Eighth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics. Proceedings of SPIE. No.6437. Society of Photo-optical Instrumentation Engineers (SPIE) , Bellingham, WA, Art. No. 64370E. ISBN 9780819465504.

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We investigate the feasibility of using iron oxide nanoparticles as a contrast agent for radiofrequency (RF) induced thermoacoustic tomography. Aqueous colloids of iron oxide (Fe3O4) nanoparticles have been synthesized and characterized. The synthesis method yielded citrate-stabilized, spherical particles with a diameter of approximately 10 nm. The complex permittivity of the colloids was measured with a coaxial probe and vector network analyzer, and the microwave absorption properties were calculated by using a relationship between the complex permittivity and absorption coefficients. Using our pulsed thermoacoustic imaging system at 3 GHz, the time-resolved thermoacoustic responses of those colloids were measured and compared to that of deionized water. Finally, two-dimensional thermoacoustic images were acquired from iron oxide colloids in a tissue phantom. The iron oxide colloids produced an enhancement in RF absorption of up to three times that of deionized water at 3 GHz. The enhancement increased rapidly with decreasing frequency of the RF excitation source. A corresponding increase in time-resolved thermoacoustic signal of more than two times was demonstrated. Our results indicate that iron oxide nanoparticles have the potential to produce enhanced thermoacoustic signals and to provide molecular imaging with functionalized contrast agents for thermoacoustic tomography.

Item Type:Book Section
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Wang, Lihong V.0000-0001-9783-4383
Additional Information:© 2007 Society of Photo-Optical Instrumentation Engineers (SPIE). We would like to thank Shih-hsun Hsu, Rui Xu, and Dr. Kai Chang for their assistance with microwave measurement. This project was sponsored by National Institutes of Health grants R01 EB000712 and R01 NS46214.
Funding AgencyGrant Number
NIHR01 EB000712
NIHR01 NS46214
Subject Keywords:Thermoacoustic tomography (TAT), contrast agent, iron oxide nanoparticle
Series Name:Proceedings of SPIE
Issue or Number:6437
Record Number:CaltechAUTHORS:20180921-100902366
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Official Citation:Xing Jin, Xing Jin, Aaron Keho, Aaron Keho, Kenith Meissner, Kenith Meissner, Lihong V. Wang, Lihong V. Wang, } "Iron-oxide nanoparticles as a contrast agent in thermoacoustic tomography", Proc. SPIE 6437, Photons Plus Ultrasound: Imaging and Sensing 2007: The Eighth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics, 64370E (13 February 2007); doi: 10.1117/12.698329;
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:89834
Deposited By: George Porter
Deposited On:26 Sep 2018 22:37
Last Modified:16 Nov 2021 00:38

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