Fig. 9A to J, shows a comparison of the temperature
increase with time when the tumor of a mouse injected with
either a suspension of nanocages (B–E) or a sham treatment of
saline solution (F–I) was irradiated with a NIR continuous
wave (CW) laser.48 The nanocages were injected via the tail
vein and allowed to accumulate in the tumor through passive
targeting for 72 h before irradiation. It is clear that in the
presence of highly absorbing nanocages the laser irradiation
resulted in a significant increase in temperature, while almost
no change was observed for the sham treatment. To confirm
that this temperature change led to tumor destruction, the
metabolism of the tumor was measured before and after
treatment with [18F] fluorodeoxyglucose positron emission
tomography (18F-FDG PET).62 The metabolic activity was
normalized by comparing it with a non-treated tumor on the
same mouse. As can be seen in Fig. 9K, only the nanocagetreated
mouse experienced a large decline in tumor metabolic
activity