Figure 5.

The relative contribution of the EPR effect and receptor-mediated targeting effect to tumor accumulation of NMs. (A) Specific accumulation of both HSA (top panels) and ATF-HSA (bottom panels) in tumors are shown in the front view of the representative mice and three-dimensional view of tumors 48 h post-injection to H22 tumor-bearing Kunming mice. (B) Dynamics of tumor targeting of HSA (blank bars) and ATF-HSA (shaded bars) on H22 tumor-bearing mice. Average concentrations of fluorescent probe (CPZ) were quantitated by non-invasive fluorescent molecular tomography at the tumor and non-tumor sites at indicated time points after injection to the tumor-bearing mice. Both HSA and ATF-HSA accumulated rapidly at the tumors sites, as seen from the data at 6 h and 12 h, with signals of 3 folds compared to the non-tumor sites. After 24 h injection, ATF-HSA showed higher tumor retention than HSA (about 2 times). At 96 h post-injection, ATF-HSA showed almost 4 times tumor accumulation compared to HSA. The data were averaged from 3 mice in each group at each time point; bars represent standard error of the mean (SEM). *Significantly higher CPZ tumor accumulation for ATF-HSA compared to that of HSA, p < 0.05.