Biodistribution of 10B for Boron Neutron Capture Therapy (BNCT) in a Mouse Model after Injection of Sodium Mercaptoundecahydro-closo-dodecaborate and l-para-Boronophenylalanine

Abstract In boron neutron capture therapy, the absorbed dose from the 10B(n,α)7Li reaction depends on the 10B concentration and 10B distribution in the irradiated volume. Thus compounds used in BNCT should have tumor-specific uptake and low accumulation in normal tissues. This study compares in a mouse model the 10B uptake in different organs as delivered by l-para-boronophenylalanine (BPA, 700 mg/kg body weight, i.p.) and/or sodium mercaptoundecahydro-closo-dodecaborate (BSH, 200 mg/kg body weight, i.p). After BSH injection, the 10B concentration was high in kidneys (20 ± 12 µg/g) and liver (20 ± 12 µg/g) but was low in brain (1.0 ± 0.8 µg/g) and muscle (1.9 ± 1.2 µg/g). After BPA injection, the 10B concentration was high in kidneys (38 ± 25 µg/g) and spleen (17 ± 8 µg/g) but low in brain (5 ± 3 µg/g). After combined BPA and BSH injection, the effect on the absolute 10B concentration was additive in all organs. The ratio of the 10B concentrations in tissues and blood differed significantly for the two co...