Biodistribution of radio-labeled non-targeted (A) and targeted (B) conjugate in nu/nu mice bearing KB xenograft tumor depicted as percentage of injected dose of dendrimer recovered per gram of organ (% ID/g ± SD). The values for different organs at 5 min, 2 h, and at 1, 4, and 7 days after delivery are the means ± SD of 3 to 5 mice.