Determination of the range of alpha particles in histological samples using a proton beam

The 70 mum-thick sliced mouse samples used in boron neutron capture therapy research are normally freeze-dried and permanently mounted on a sticky tap e. Such a preparation alters the tissue density and makes it impossible to correctly determine the ranges of the alpha particles from the B-10(n,alpha )Li-7 reaction. Proton radiography utilising etched-track detectors can be successfully used for the density determination of these histological sampl es. The technique is based on the measurement of different energy losses in different tissues. A computer simulation was made in order to estimate the efficiency and sensitivity of this technique. Some typical values for tiss ue density and elemental composition were taken from the SRIM program datab ase. The applicability of this technique was illustrated and ranges of alph a particles in a histological sample of tumor-bearing mouse were determined using proton ranges as a reference. (C) 2001 Elsevier Science Ltd. All rig hts reserved.