Improved imaging performance of a semiconductor Compton camera GREI makes for a new methodology to integrate bio-metal analysis and molecular imaging technology in living organisms

We have constructed the second prototype of the semiconductor Compton camera GREI that enables spectroscopic imaging of wide energy-range gamma-rays. The improved imaging performance has been demonstrated by an imaging experiment with a tumor-baring live mouse, where we were able to obtain the distribution images of the Cu-64-labeled antibody to the implanted three tumor sites of different cell lines, together with that of Zn-65, which was simultaneously administered as ZnCl2 solution. The imaging performance has been compared with that of the primary prototype of GREI, and the importance of the improvement for the simultaneous imaging of multiple radiotracers has been revealed. The methodology offered by GREI is expected to make a unique contribution toward establishing a new viewpoint for understanding life phenomena.