Induction of DNA double-strand breaks by 111
In-BnDTPA-F3. The 231-H2N cells were X-irradiated (IR, 4 Gy) or exposed to 111In-BnDTPA-F3 (0 to 5 μM, 20.6 MBq/nmol), an equivalent amount of 111In chloride, or cold, unlabeled BnDTPA-F3 for (A) 2 h or (B) 24 h. Cells were fixed and stained for γH2AX. The number of γH2AX foci per cell was determined. Results are expressed as mean ± SEM, n = 200 per condition.(C) The 231-H2N cells were exposed to 111In-BnDTPA-F3 (2 μM) with varying specific activities (0 to 6 MBq/μg) for 2 h and treated as above.