Tunable, biodegradable gold nanoparticles as contrast agents for computed tomography and photoacoustic imaging

Traditional computed tomography (CT) contrast agents, such as iodine-containing small molecules (omnipaque), have limitations in some applications. The development of nanotechnology has made it possible to develop CT contrast agents based on this technology. In this study, a large number of surface functional groups of the fifth-generation polyamide-amine dendrimer (P5-NH2) were applied to functionally modify polyethylene glycol (PEG), targeting molecules, or drugs, which were used as the carrier of CT contrast agents. With the help of sodium borohydride (NaBH4), there was a rapid reduction. The fluorescein thiocyanate (FT) and PEG modified with lactobionic acid (PEG-LA) weres connected before gold coating to obtain gold nanoparticles coated with targeted dendrimer (Au(P5-LA)DENPs). In the experiment, the gold nanoparticles were characterized, and the liver cancer nude mouse model was established, so as to analyze the CT imaging performance of the material. Besides, the above was applied in the motor function of children with cerebral palsy, and the improvement effect of CT imaging combined with transcranial magnetic stimulation based on the preparation of nanomaterials on the movement function of children was analyzed and demonstrated with the help of graph theory. The results showed that the average particle size of gold nanoparticles was 1.88 nm. Within the range of 5 °C–50 °C and pH = 4–7, the physical properties of the aqueous solution of this material were stable. What’s more, the cell activity still exceeded 80% when the material concentration reached 2000 nm. The nude mouse model of liver cancer indicated that the CT imaging based on this material enhanced the image contrast effect of the tumor part, and the material had no obvious toxic and side effects. CT imaging based on the preparation of nanomaterials can promote transcranial magnetic stimulation to accelerate the efficiency of brain movement, accelerate the global and local information exchange and integration speed of brain network, thereby improving the movement function of children.

Download Full-text

CMR 2007: 8.03: Gold nanoparticles as contrast agents for MRI and X-ray computed tomography imaging

Contrast Media & Molecular Imaging ◽

10.1002/cmmi.195 ◽

2007 ◽

Vol 2 (6) ◽

pp. 292-293

Author(s):

S. Roux ◽

C. Alric ◽

J. Taleb ◽

C. Mandon ◽

C. Billotey ◽

...

Keyword(s):

Computed Tomography ◽

Gold Nanoparticles ◽

Contrast Agents ◽

Computed Tomography Imaging ◽

X Ray ◽

Tomography Imaging ◽

X Ray Computed

Download Full-text

Cyclodextrin-Based Contrast Agents for Medical Imaging

Molecules ◽

10.3390/molecules25235576 ◽

2020 ◽

Vol 25 (23) ◽

pp. 5576

Author(s):

Yurii Shepelytskyi ◽

Camryn J. Newman ◽

Vira Grynko ◽

Lauren E. Seveney ◽

Brenton DeBoef ◽

...

Keyword(s):

Computed Tomography ◽

Medical Imaging ◽

Contrast Agents ◽

Single Photon ◽

Photoacoustic Imaging ◽

Photon Emission ◽

Emission Computed Tomography ◽

Naturally Occurring ◽

Positron Emission ◽

Photon Emission Computed Tomography

Cyclodextrins (CDs) are naturally occurring cyclic oligosaccharides consisting of multiple glucose subunits. CDs are widely used in host–guest chemistry and biochemistry due to their structural advantages, biocompatibility, and ability to form inclusion complexes. Recently, CDs have become of high interest in the field of medical imaging as a potential scaffold for the development of a large variety of the contrast agents suitable for magnetic resonance imaging, ultrasound imaging, photoacoustic imaging, positron emission tomography, single photon emission computed tomography, and computed tomography. The aim of this review is to summarize and highlight the achievements in the field of cyclodextrin-based contrast agents for medical imaging.

Download Full-text

Investigation of imaging properties of novel contrast agents based on gold, silver and bismuth nanoparticles in spectral computed tomography using Monte Carlo simulation

Polish Journal of Medical Physics and Engineering ◽

10.2478/pjmpe-2020-0003 ◽

2020 ◽

Vol 26 (1) ◽

pp. 21-29

Author(s):

Maryam Sadeghian ◽

Parisa Akhlaghi ◽

Asghar Mesbahi

Keyword(s):

Computed Tomography ◽

Gold Nanoparticles ◽

Monte Carlo ◽

Contrast Agents ◽

Ct Number ◽

Bismuth Nanoparticles ◽

Iodinated Contrast ◽

Spectral Computed Tomography ◽

Iodinated Contrast Agent ◽

Imaging Properties

AbstractIn the present paper, some imaging properties of nanoparticles-based contrast agents including gold, bismuth, and silver were assessed and compared with conventional (iodinated) contrast agent in spectral computed tomography (CT). A spectral CT scanner with photon-counting detectors (PCD) and 6 energy bins was simulated using the Monte Carlo (MC) simulation method. The nanoparticles were designed with a diameter of 50 nm at concentrations of 2, 4, and 8 mg/ml. Water-filled cylindrical phantom was modeled with a diameter of 10 cm containing a hole with a diameter of 5 cm in its center, where was filled with contrast agents. The MC results were used to reconstruct images. Image reconstruction was accomplished with the filtered back-projection (FBP) method with hamming filter and linear interpolation method. CT number and contrast-to-noise ratio (CNR) of all studied contrast materials were calculated in spectral images. The simulations indicated that nanoparticle-based contrast agents have a higher CT number and CNR than the iodinated contrast agent at the same concentration and for all energy bins. In general, gold nanoparticles produced the highest CT number and CNR compared to silver and bismuth nanoparticles at the same concentration. However, at low energies (below 80 keV), silver nanoparticles performed similarly to gold nanoparticles and at high energies (120 keV), bismuth nanoparticles can be a good substitute for gold nanoparticles.

Download Full-text