Abstract
The present study explores the use of α-particleemitting, bone-seeking agents as candidates for targeted radiotherapy. Actinium and thorium 1,4,7,10 tetraazacyclododecane N, N’, N”, N”’ 1,4,7,10-tetra(methylene) phosphonic acid (DOTMP) and thorium-diethylene triamine N, N’, N” penta(methylene) phosphonic acid (DTMP) were prepared and their biodistribution evaluated in conventional Balb/C mice at four hours after injection. All three bone-seeking agents showed a high uptake in bone and a low uptake in soft tissues. Among the soft tissue organs, only kidney had a relatively high uptake. The femur/kidney ratios for 227Th- DTMP, 228Ac-DOTMP and 227Th-DOTMP were 14.2, 7.6 and 6.0, respectively. A higher liver uptake of 228Ac-DOTMP was seen than for 227Th-DTMP and 227Th-DOTMP. This suggests that some demetallation of the 228Ac-DOTMP complex had occurred. The results indicate that 225Ac-DOTMP, 227Th- DOTMP and 227Th-DTMP have promising properties as potential therapeutic bone-seeking agents.
- Received August 28, 2003.
- Accepted October 27, 2003.
- Copyright© 2004 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved
