Fig. 3

Fluorescence imaging of mouse vasculature in the NIR-II window (excitation = 915 nm, 1250 nm long-pass filter, 100 ms expose time). a NIR-II imaging of hind limb vasculature. b NIR-II imaging of abdominal vessels. c NIR-II imaging of mouse brain through intact scalp and skull vasculature. d Lymph node imaging after injection of NIC-ER in footpad, white arrows indicate the popliteal lymph node