Quantitative whole-body autoradiography: recommendations for the standardization of the method

The objective of this article is to identify the best conditions for preparing, handling, and exposing radioactive sections by using the Fujix BAS 2000 system for quantitative radioluminography. Regarding the influence of thickness of sections, thicker sections may allow shorter exposure times due to the increased radioactivity, but on the other hand they take more time for the freeze-drying process, resolution will be reduced, and the recovery of radioactivity will be lower due to increased self-absorption particularly in organs like bones or teeth. The pretreatment of the sections should depend on the method of exposure. Powdering with talcum is the most recommendable method when vacuum packaging the imaging plates and sections. Spraying with Nobecutan is recommended when using the cartridge method. Particularly for low concentrations, the vacuum-contact method should be the method of choice. To avoid a flare effect, the geometrical arrangement of the sections on the imaging plate (IP) should always be vertical to the scanning direction of the laser. An exposure time longer than 10 days is not recommended and the time between the end of exposure and start of scanning should be as short as possible. In order to reduce the background signal, it is necessary to expose the IPs in a shielding box in a cold environment. No positive chemographic effects of sections were found.