title: Quantitative imaging of gold nanoparticle distribution in a tumor-bearing mouse using benchtop x-ray fluorescence computed tomography.
abstract: X-ray fluorescence computed tomography (XFCT) is a technique that can identify, quantify, and locate elements within objects by detecting x-ray fluorescence (characteristic x-rays) stimulated by an excitation source, typically derived from a synchrotron. However, the use of a synchrotron limits practicality and accessibility of XFCT for routine biomedical imaging applications. Therefore, we have developed the ability to perform XFCT on a benchtop setting with ordinary polychromatic x-ray sources. Here, we report our postmortem study that demonstrates the use of benchtop XFCT to accurately image the distribution of gold nanoparticles (GNPs) injected into a tumor-bearing mouse. The distribution of GNPs as determined by benchtop XFCT was validated using inductively coupled plasma mass spectrometry. This investigation shows drastically enhanced sensitivity and specificity of GNP detection and quantification with benchtop XFCT, up to two orders of magnitude better than conventional x-ray CT. The results also reaffirm the unique capabilities of benchtop XFCT for simultaneous determination of the spatial distribution and concentration of nonradioactive metallic probes, such as GNPs, within the context of small animal imaging. Overall, this investigation identifies a clear path toward in vivo molecular imaging using benchtop XFCT techniques in conjunction with GNPs and other metallic probes.
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Nivedh
authors.initials: N
authors.lastname: Manohar
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Reynoso
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Parmeswaran
authors.initials: P
authors.lastname: Diagaradjane
authors.affiliation: Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Sunil
authors.initials: S
authors.lastname: Krishnan
authors.affiliation: Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.|Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Cho
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D003287:Contrast Media / Q000737:chemistry / Q000494:pharmacology; D006046:Gold / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D008297:Male; D053768:Metal Nanoparticles / Q000737:chemistry*; D051379:Mice; D009374:Neoplasms, Experimental / Q000000981:diagnostic imaging*; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging*; D013052:Spectrometry, X-Ray Emission / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D006046:Gold