A novel photon radiation detector system for in vitro biokinetic measurements

This study evaluates a novel photon radiation detector system for in vitro biokinetic measurements.

A cell-culture well can be considered to consist of two different compartments: the cells and the medium. By placing the well on a lead-collimated scintillation (NaI(T1)) detector, changes in activity distribution between the compartments will result in changes in count rates owing to the efficiency ratio (ER) between the cells and the medium. The ER depends on differences in detection solid angles for the compartments and differences in attenuation of photons emitted from the compartments. Evaluation of the optimal measuring geometries for the detector system was done by Monte Carlo (MC) simulations. The detector system was tested in two different in vitro situations.

The MC simulations showed that the most optimal detector system was obtained by using a lead-collimated well crystal. Both the MC simulations and the experiments have proven the usability of the system.

The detector system was demonstrated to be of value for biokinetic studies. The cellular binding of radiolabeled substances can be determined with high precision, and real-time measurements can be performed on a cell culture without harvesting the cells.