Preparation of New Scintillation Imaging Material Composed of Scintillator-Silica Fine Powders and its Imaging of Tritium.

A new scintillation imaging material [scintillator-silica fine powder (FP)] was prepared using silica FPs and scintillator-encapsulating silica nanoparticles (NPs) (scintillator-silica NPs). The wt% values of scintillator-silica NPs on the scintillator-silica FPs were 38, 43, 36 and 44%. Scintillation images of H-3, Ni-63, S-35, P-33, Tl-204, Sr-89 and P-32 dropped on the scintillator-silica FPs were obtained at about 37 kBq per 0.1-10 mu l with a charge-coupled device (CCD) imager for a 5 min exposure. In particular, high-intensity CCD images of S-35 were selectively obtained using the 2.25, 4.77 and 10 mu m silica FPs with scintillator-silica NPs owing to the residual S of dimethyl sulfoxide in the preparation. Scintillation images of H-3 at 1670 +/- 9 Bq/0.5 mu l and 347 +/- 6 Bq/0.5 mu l dropped in a 2 mm hole on the scintillator-silica FPs (6.78 and 10 mu m) were also obtained using the CCD imager for a 2 h exposure.