Simultaneous imaging of bio-metal and molecular radiotracers in the body is now possible using a gamma-ray emission came

Jul 25, 2013
Simultaneous imaging of bio-metal and molecular radiotracers in the body is now possible using a gamma-ray emission came
Figure 1: The GREI-II system is capable of generating images of bio-metal radiotracers and molecular PET tracers at the same time, allowing the complex interactions between metals and their associated molecules to be seen for the first time. Royal Society of Chemistry

Trace metals in living organisms play a variety of important roles in many processes, including gene expression and the development of diseases such as cancer. It is possible to image the behavior of these 'bio-metals' by following radioactive tracers injected into the body. However, analyzing the corresponding expression of metal-associated molecules in the body using technologies like positron emission tomography (PET) has so far been impossible due to differences in the kinds of radiotracers used by these techniques. Shuichi Enomoto, Shinji Motomura and colleagues at the RIKEN Center for Life Science Technologies have now developed a way to simultaneously image a wide range of bio-metal and PET scan radiotracers in the body through the use of a semiconductor Compton camera called GREI-II.

"Our first gamma-ray emission imaging camera was developed for the imaging of multiple tracers and enabled us to track bio-metals in ," explains Motomura. "We used it in the detailed exploration of molecules, which led us to the idea of integrating bio-metal analysis and PET technology."

The gamma-ray emission imaging (GREI) system works by gathering information about emitted by the radiotracers through measurement of the changes in direction and energy of the gamma-ray photons as they hit . By tracing the trails produced by this 'Compton scattering', the source of gamma rays can be located, and the different radioisotopes in each tracer can be distinguished by the gamma-ray wavelength (Fig.1).

"The half-lives of the molecular imaging agents for PET are very short," explains Motomura. "To realize the simultaneous and efficient imaging of the PET agents and bio-metal tracers, we had to improve the sensitivity of the camera and the speed of data processing."

Enomoto's team tested their GREI-II technology by collecting images from in live mice using copper-64 and zinc-65 radiotracers. Results showed that copper was found in abundance at tumor sites, whereas zinc collected in greater quantities in the liver, pancreas and kidneys. Comparisons with images from the first GREI system showed that the new system had less background noise and greater clarity. GREI-II is also capable of imaging at more than ten times the speed.

"The GREI-II images cannot be obtained by other imaging systems because their gamma-ray energies are high and the energy range is too wide," explains Motomura. "We expect GREI will be able to help us understand the intricate mechanisms of many diseases in the future."

Explore further: Precise ages of largest number of stars hosting planets ever measured

More information: Journal of Analytical Atomic Spectrometry 28, 934–939 (2013).

Related Stories

SPECT/MR molecular imaging system makes its debut

Jun 11, 2013

The Society of Nuclear Medicine and Molecular Imaging's 2013 Annual Meetingmarks the unveiling of the successful application of a new preclinical hybrid molecular imaging system—single photon emission tomography and magnetic ...

FDA clears Siemens' 2-in-1 medical scanner

Jun 10, 2011

(AP) -- The Food and Drug Administration says it has cleared the first medical imaging device to simultaneously perform two powerful scans used to diagnose a wide variety of diseases and ailments.

New marker substance for cancer cells

Jul 04, 2013

Scientists from ETH Zurich have developed a new substance that enables certain tumour types to be rendered visible in high resolution using positron emission tomography. The so-called tracer has successfully ...

Most distant blazar is a high-energy astrophysics puzzle

Apr 18, 2013

(Phys.org) —Blazars are the brightest of active galactic nuclei, and many emit very high-energy gamma rays. New observations of the blazar known as PKS 1424+240 show that it is the most distant known source ...

FDA approval for Siemens PET Scan - MRI combo

Jun 13, 2011

(Medical Xpress) -- The Siemens Biograph mMR system, offering both a PET scan and an MRI that work simultaneously, has been given approval by the FDA. The idea behind this machine and the ability to run both tests at the ...

Recommended for you

The discovery of the molecule Si-C-Si in space

21 hours ago

The space between stars is not empty—it contains a vast reservoir of diffuse material with about 5-10% of the total mass of our Milky Way galaxy. Most of the material is gas, but about 1% of this mass (quite ...

Hubble view of a nitrogen-rich nebula

21 hours ago

This NASA/ESA Hubble Space Telescope image shows a planetary nebula named NGC 6153, located about 4,000 light-years away in the southern constellation of Scorpius (The Scorpion).

Is the universe ringing like a crystal glass?

Jun 26, 2015

Many know the phrase "the big bang theory." There's even a top television comedy series with that as its title. According to scientists, the universe began with the "big bang" and expanded to the size it ...

Improved sensors help navigate gravity waves

Jun 26, 2015

Efforts to detect gravitational waves—which were first predicted by Albert Einstein nearly 100 years ago—are advancing with international researchers including UWA researchers boosting the sensitivity ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.