Whole body fluorescence accumulation and distribution was assessed in male athymic nude mice 8 weeks of age using an IVIS Spectral CT (Perkin Elmer). Mice were anesthetized with inhaled isoflurane and baseline images were acquired. Then, mice were intraperitoneally or subcutaneously injected with 100 μL of saline or 5 μM LUXendin762. Images were collected using a broad excitation and emission series combination ranging from 640 to 675 nm and 680 to 760 nm, respectively at 30 minutes and 1 hour post injection. At the end point, animals were sacrificed, and tissues (pancreas, heart, brain, lung, kidney, liver, and spleen) were harvested for ex vivo fluorescent analysis. Spectral unmixing and quantification were analyzed using Living Image Software.