BRIC Cyclotron now producing more PET probes

We are proud to announce that the BRIC Cyclotron and radiochemistry facility is now capable to provide more PET imaging probes beyond the commonly available ¹⁸F-FDG agent. More than ten PET tracers have been added to the radiotracer menu that are now available to all investigators (Table-1). The expanded menu will greatly enhance our molecular imaging capability and facilitate many cancer and neuroscience research.

The BRIC cyclotron facility is equipped with a GE 16.5MeV PETtrace cyclotron, hot cells and minicells for radiotracer synthesis. In addition, the core also has a GMP level clean room, two dispensing cells, and QC setup to provide probes for human imaging research and clinical trials. The newly installed cyclotron has 6 targets which can be used to produce various radioisotopes including F-18 (two targets), C-11(one target), O-15 (one target), N-13 (one target), and one target reserved for future radio-metal production. Under the core Director, Dr. Zibo Li, the facility has made tremendous progress since the installation of the cyclotron facility. Many new imaging probes are now available for preclinical imaging research, including F-18 labeled FLT (tumor proliferation), FMISO (tissue hypoxia), HX4 (tissue hypoxia), fallypride (dopamine receptor imaging), and PBR111 (neuroinflammation), C-11 labeled raclopride (dopamine receptor imaging) N-13 labeled ammonium (cardiac perfusion), and O-15 labeled water (cerebral blood flow).

¹⁸F-FLT has been used widely in oncology for tumor proliferation [1]. It has been reported that it is superior to FDG for detecting recurrent high grade brain tumors [2], and have been used to predict treatment outcome. An example of PET imaging with ¹⁸F-FLT is shown in Figure-1. ¹⁸F-FMISO and ¹⁸F-HX4 are both targeting tumor hypoxia [3, 4]. ¹⁸F-FMISO is the mostly used hypoxia imaging marker with several clinical trials for head and neck cancer, lung cancer, cervical cancer, and brain tumors. An image example is shown in Figure 2. ¹⁸F-HX4 is more hydrophilic compared to FMISO, resulting faster blood clearance and less waiting time after injection. Along with ¹⁸F-FDG, the core can provide comprehensive molecular imaging probes for cancer research.

Fig. 2. Tumor hypoxia study using ¹⁸F-FMISO PET imaging and autoradiography imaging compared to hypoxia immunostaining image.

¹⁸F-PBR111 is a relatively new PET probes with high affinity and selectivity for the translocator protein (TSPO) expressed on activated glia cells. It has been used in several neuroinflammation animal models [5]. Figure 3 shows an example of using PBR111 to image neuroinflammatory mouse model. Fallypride and raclopride both are widely used PET tracers for imaging dopamine D2 receptors with F-18 or C-11 radiolabeling [6]. They can be used to monitor changes on Dopamine D2 receptor related diseases such as Parkinson, drug addiction, and epilepsy study [7].