3,3'-Diheptyloxacarbocyanine iodide (DiOC7(3)) is a green membrane potential probe with excitation and emission wavelengths of 450-490 nm and 510-520 nm, respectively. It is useful in quantifying vascular densities [1].

Identification of Tumor Vasculature (Frozen Section): Guidelines (Following is our recommended protocol. This protocol only provides a guideline, and should be modified according to your specific needs) [1].

1. Administer the dye to mice via lateral tail vein injection at a dose of 1 mg/kg in a 50 μL volume.
2. Sacrifice the animals 5 minutes post-administration, excise the tumors immediately, and freeze them at -20°C.
3. Rewarm 10 μm thick frozen sections to room temperature and allow them to air dry.
4. Image using a microscope with 100W mercury lamp illumination and an epifluorescence condenser (excitation at 430-490 nm, emission at 510-520 nm).