Novel approaches for high contrast, deep tissue, in vivo fluorescence biomedical imaging are based on infrared-emitting nanoparticles working in the so-called second biological window （1,000-1,400 nm）. This allows f...Novel approaches for high contrast, deep tissue, in vivo fluorescence biomedical imaging are based on infrared-emitting nanoparticles working in the so-called second biological window （1,000-1,400 nm）. This allows for the acquisition of high resolution, deep tissue images due to the partial transparency of tissues in this particular spectral range. In addition, the optical excitation with low energy （infrared） photons also leads to a drastic reduction in the contribution of autofluorescence to the in vivo image. Nevertheless, as is demonstrated here, working solely in this biological window does not ensure a complete removal of autofluorescence as the specimens diet shows a remarkable infrared fluorescence that extends up to 1,100 nm. In this work, we show how the 1,340 nm emission band of Nd3. ions embedded in SrF2 nanoparticles can be used to produce autofluorescence free, high contrast in vivo fluorescence images. It is also dem- onstrated that the complete removal of the food-related infrared autofluorescence is imperative for the development of reliable biodistribution studies.展开更多
文摘Novel approaches for high contrast, deep tissue, in vivo fluorescence biomedical imaging are based on infrared-emitting nanoparticles working in the so-called second biological window （1,000-1,400 nm）. This allows for the acquisition of high resolution, deep tissue images due to the partial transparency of tissues in this particular spectral range. In addition, the optical excitation with low energy （infrared） photons also leads to a drastic reduction in the contribution of autofluorescence to the in vivo image. Nevertheless, as is demonstrated here, working solely in this biological window does not ensure a complete removal of autofluorescence as the specimens diet shows a remarkable infrared fluorescence that extends up to 1,100 nm. In this work, we show how the 1,340 nm emission band of Nd3. ions embedded in SrF2 nanoparticles can be used to produce autofluorescence free, high contrast in vivo fluorescence images. It is also dem- onstrated that the complete removal of the food-related infrared autofluorescence is imperative for the development of reliable biodistribution studies.
