The high brightness, long absorption and emission wavelength, as well as the superior stability of DIPT-ICF NPs makes it excellent imaging contrast agent for implementing the whole organ transplantation surgery. Before applying DIPT-ICF NPs for in vivo experiment, the penetration depth and imaging resolution of DIPT-ICF NPs were evaluated in vitro through tissue phantoms . As shown in Fig. , pre-covering DIPT-ICF NPs filled capillary tubes with chicken breast tissue, the signal background ratios (SBRs) of NIR-I and NIR-II imaging were measured. The fluorescence signals intensity collected from both NIR-I and NIR-II channel were obvious when the chicken breast tissue thickness is smaller than 2 mm (Fig. and). When the thickness of chicken breast tissue was increased to 3 mm, NIR-II imaging exhibited its advantage in penetration depth with SBRs of NIR-II significantly higher than that of NIR-I (P < 0.05) (Fig. ). To further evaluate the potential of DIPT-ICF NPs for angiography in vivo, subcutaneous fluorescent angiography was performed on mice abdomens under different laser-filter arrays, such as 808 nm laser combined with 900 nm long pass filter (LP) and 1319 nm LP, and 980 nm laser combined with 1020 nm LP, 1100 nm LP, and 1319 nm LP, respectively (Fig. and). In general, the combination of 980 nm laser excitation and 1319 nm LP affords higher resolution angiography images and better SBR, which can be assigned to the higher brightness and deeper penetration depth in this wavelength region (Fig. and).