Visualization of zinc dynamics in intact plants using positron imaging of commercially available 65Zn

Abstract

Background: Positron imaging can be used to non-destructively visualize the dynamics of a positron-emitting radionuclide in vivo, and is therefore a tool for understanding the mechanisms of nutrient transport in intact plants. The transport of zinc, which is one of the most important nutrient elements for plants, has so far been visualized by positron imaging using 62Zn (half-life: 9.2h), which is manufactured in the limited number of facilities that have a cyclotron. In contrast, the positron-emitting radionuclide 65Zn (half-life: 244days) is commercially available worldwide. In this study, we examined the possibility of conducting positron imaging of zinc in intact plants using 65Zn. Results: By administering 65Zn and imaging over a long time, clear serial images of 65Zn distributions from the root to the panicle of dwarf rice plants were successfully obtained. Conclusions: Non-destructive visualization of zinc dynamics in plants was achieved using commercially available 65Zn and a positron imaging system, demonstrating that zinc dynamics can be visualized even in facilities without a cyclotron.